Hi, I'm Rebecca. In this lesson, you will
learn the difference between two very popular English tenses, and they are the past simple,
which is a basic tense, and the present perfect, which is a more advanced tense. This lesson
is part of a series of classes on English verb tenses, created by www.engvid.com , to
help you master all of the English verb tenses, step by step. So, I do have individual classes
on each of these tenses, and if you've already watched them, that's great. You can watch
this lesson, and it will help you to review and deepen your understanding of the difference
between these two important and commonly used tenses. And, if you haven't watched the separate
lessons, you can still watch this lesson and use it as a kind of introduction and overview
of these two tenses, and then you can go and watch the individual lessons. Alright? So,
are you ready to start? Let's go. So, the past simple talks about what? The
past! Yes. It talks about an action that started and ended in the past. That's basically it.
For example, "I worked yesterday." Okay? It's just telling you about something that I did
in the past. It's finished, it's over. The present perfect is a little bit different.
It connects the past and the present. For example, "I have worked all day, so I'm tired."
Now, it's saying, "I have worked", I did something all day and as a result, there is some effect
now. And that effect is that I'm tired. Okay? So, there is a connection between the past
and the present. Something that you did in the past has a result or effect now. Whereas
here, you're just saying, you know, that thing happened. That's it, okay? For example, "They forgot my birthday." Okay?
They forgot my birthday last week, alright? To be more specific, a time in the past. It's
finished, it's over, they forgot it, it's over, alright? Here, I could have said, "They
have forgotten my birthday many times." Alright? So, it's in the past until now, they've forgotten
it and they still forget it, so it's connecting the past and the present, whereas here, it's
just talking about the past. Alright? See that difference? That's important to understand. Here, we could say, "He lost his bag last
week." Okay? But, when we say, "He lost his bag", it just tells us what happened last
week. We don't know what the situation is now. Here, we say, "He has lost his bag."
When we say, "He has lost his bag", you know right away and immediately that he lost it,
and it's still lost. It's still true. This sentence is still true. Here, maybe he lost
it on Monday and he found it on Tuesday. So, we don't know 100% that that bag is still
lost, we just know it happened. We don't know if its still true. But as soon as you say,
"He has lost", see the difference here, "He has lost", versus just, "He lost", here we
know it's still true. And whatever happened before is still true now, it has an effect
now which means that he doesn't have his bag now. But here, maybe he found it, maybe he
didn't. We don't know, okay? So, that's one important difference. This is just about the
past, and this connects the past and the present. Let's move on. So, the past simple talks about an action
in the past, and the focus is also on the past. For example, "She did her homework.",
okay? We're just talking about what she did. She ate dinner, she did her homework, these
are things that happened and they happened then and they're finished and they're over,
right? But this one, present perfect, there's an action in the past, but the focus is on
now. For example, if we say instead of, "She did", we say "She has done her homework",
it means she's free now. She can do other things now. That's what we're sort of suggesting.
Or here, we just say, "She ate dinner", okay? She did this, she did that, that's it, its
finished. But here, if we say, "She has eaten dinner", what does that mean? Okay, she's
not hungry now. We don't have to give her anything to eat now, okay? So, there is something
that has an effect in the present, because of something that was done in the past. So,
the focus - the action was in the past, but the focus is really on something now. Next, here with the past simple, we talk about
definite times. We say when something happened. For example, "I visited New York in 2012.",
okay? Visited, and we say when. We have a definite time. Here, with present perfect,
we can't use a definite time. We actually cannot use it. We're not allowed to use it
with this tense. So here, you will see sentences like this, "I have visited", okay, "I have
visited New York". It means in my life, but I'm not saying when. I'm just saying that
I have done that. But here, I'm saying that I did it and I'm saying when I did it. So
here, the time is definite, and here it's indefinite. Let's look at some more differences
between these very commonly used tenses. Another very important difference is that
we use the past simple to talk about a finished time. And we use the present perfect to talk
about an unfinished time. Now, in the sentences themselves, we might mention a time marker,
which tells us that something is finished or unfinished, or we might not. Let's look
at some examples and then you'll understand exactly how it works. So, in this one, "She lived in London from
2015 to 2018." So, what's the past simple? "She lived", right? And "from 2015-2018" is
the finished time. This time is over, it's finished. So, that's fine. We can use it in
past simple. But here, we say, "She's lived", which means she has lived, "in London since
2015." "Since 2015" means it started at that time, but it's not finished yet. Since 2015
till now. So, it includes the past and the present and it's unfinished, okay? Here, it's
finished. It's over. But here, since that time, since that point in time, till now,
and including now. So, this is considered an unfinished time. So very often, with the
present perfect tense, you'll see this word being used. Since 2015, since 5:00, since
this morning. Since I was young, okay? Something started in the past and it's unfinished. We
can also use the word "for". You will see that very often with this perfect tense, present
perfect. So, we could say, "She's lived in London for three years." Okay, for three years.
She started living in London three years ago and she still lives in London, okay? So, that's
what we mean by unfinished time. So, in present perfect, either you don't mention the time,
but if you mention a time, it has to be some expression that is - that shows that it's
unfinished, okay? Let's look at some more examples. "He didn't call me yesterday." So, "He didn't
call", this is past simple, "yesterday" is our finished time, because yesterday's finished,
it's over. But here, in present perfect, we have, "He hasn't called me yet." "He hasn't
called", this is our present perfect, but "yet" is one of those words which you can
use with the present perfect. Because what does "yet" mean? It means till now. From the
past till now. So, this is okay to use. You could also just say, "He hasn't called me".
That's okay. So, you don't have to mention the time. But, if you mention a time, make
sure it's a word which is - includes now, alright, which is unfinished. Let's look at
some more examples. "We completed the project last week." "We
completed", past simple, "last week", a finished time. Or here in present perfect, we could
say, "We've already completed the project." "We have already completed". So, "already"
is another word that you see very often with the present perfect. Alright? There we go. Here's one last example, "I met Joe last month."
"I met", past simple, "last month", it's over, it's a finished time, right? But here, we
could say, "I've met", this is our present perfect, "I've met Joe recently." Okay? So,
"recently" is another word that is representative of what? An unfinished time. Recently means
the time from not that long ago till now and including now. Alright? So, the important
thing to remember is that with present perfect, either don't mention a time, but if you mention
a time, make sure it's an unfinished time. The most common mistake that's made here between
these two points is that people use the present perfect and then they mention a finished time.
So, the mistake is, for example, "She's lived in London from 2015 to 2018." No, that would
be wrong. Or to say, "He hasn't called me yesterday." No. Okay? Because if you mention
any finished time, use past simple. That's it, don't worry about present perfect because
you can't use it in that context. Now, let's look at questions and how they
are different in the past simple tense and in the present perfect tense. So, in past
simple, we would ask a question like this, "When did you _________?", something. But
in present perfect, we could ask, "How long have you ________?" Okay? Let's look at the
difference. When we say, "When did you" in past simple, we're talking about a point in
time in the past. When did you do something? But when we say, "How long have you", we're
talking about a length of time that started in the past and continues till now, right?
So, let's see how the questions will change based on what we're trying to find out, okay,
with our question. So, for example, here we would say, "When
did you get married?" Okay? I'm asking in which year or which month or whatever. When
did you get married? Okay? That's going to give me an answer at a point in time in the
past. Here, I would say, "How long have you been married?" Okay? That means you got married
and now you're still married, so how long have you been married? I want to know about
the length of time, not the point in time when it started, but how long it continued. Here, we would say, "When did you start this
job?" Last month, last year? Okay? A point in time in the past. Here, we would ask, "How
long have you had this job?" You started at some point and you still have this job, so
what's the length of time? I've had this job for two months, three years, whatever. Okay? Here, we would ask, "When did you move to
Boston?" Here, we would say, "How long have you lived in Boston?" Okay? Are you starting
to see the difference, starting to feel the difference? Okay. Here, we would say, "When
did you meet Mary?" And on this side, "How long have you known Mary?" Okay? See the difference?
"When did you join university?" Okay? Last year, two years ago, whatever. A point in
time in the past. Or, "How long have you been in university?" What's the length of time?
Is it one year, two years, three years, okay? So, this is another very important difference
between these two tenses. So, one way you can know that is if you need to use the word
"when", then always use past simple, because the question "When?" demands an answer which
is a point in time in the past. So, whenever you have that word, then you know, I'm just
going to use past simple. I cannot use present perfect. Now, let's take a quick look at the structure
of these two tenses. In my individual lessons on these tenses, I go into much more detail
about how to structure and form these tenses. We look at the positive sentence, the negative
sentence, and the questions in detail. And, if you've already seen that, then this will
be like a little review for you. If you have not watched the individual lessons, then this
is just a quick overview for you. So, let's start with the past simple. How
do we structure that? We take the subject, which is I, You, We, They, He, She, It, etc.,
and we add the past simple form of the verb. Now, the past simple form of the verb could
be for a regular verb or an irregular verb. A regular verb, for example, is this one:
worked. Work becomes worked. So, with a regular verb, you're usually just adding -ed or -d
to make it in the past. With an irregular verb like the verb "to go", when it becomes
past simple verb, it just changes completely sometimes, like this one, from "go" to "went".
Sometimes, it doesn't change it all, like "put" and "put". And that's why those are
irregular. So, in English, you know there are some regular
verbs and irregular verbs, and they behave differently. So, with the past simple tense,
we're just taking the subject + the past simple form of the verb. So, here's an example, "I
worked", or "They went". This is with the regular verb, this is with the irregular one,
okay? If we want to make that negative, it would become, "He didn't work", or "They didn't
work", or "It didn't work." And you see a change here, it goes back to that base form
of the verb, alright? Or, if it was with the verb "to go", it would become, "He didn't
go", "We didn't go", alright? Again, watch the full lesson if you don't understand any
part of this. It's not a problem, it's important for you to understand this very well. If we're
making a question, we would say, "Did they work?" Again, we're coming back to that base
form of the verb. Did he work? Did it work? Etc. Okay? So, that's the past simple. When we're looking at the present perfect,
we have a little bit more to pay attention to. Here, we have the subject. Again, "I,
You, We, They", etc. + a helping verb, "have" or "has", which you need to know, alright?
And we're using the past participle. The past participle for a regular verb is just this
same form as the past simple verb, alright? So, we see it here. Here, we see "worked,
here we see "worked". It's a regular verb. The past participle for an irregular verb
like "go" is what's usually called like the third form, or verb three sometimes they call
it. So, for "go" for example, we would have "go", "Everyday, I go." "Yesterday, I went."
But I have gone, so this is that third form, which is called past participle. Again, study
that in detail if you need to, and if you don't understand it, just practice it a little
bit. Check in the back of any good grammar book to understand what is the past participle
form of those irregular verbs. But, let's look at the structure now. So basically,
we'll have "I, You, We, or They" have worked. "I have worked very hard this week." Or, "He
has gone to the supermarket". "He has gone", "She has gone", "It has gone", okay? Like
that. And of course, we can also contract these and shorten them, which again, I explain
the full lesson, alright? But let's look at now the negative form. "They haven't worked
all week", or, "They haven't gone to the supermarket", or, "He hasn't gone out", okay? When we make
a question, we change the order. "Have they gone out?" "Has he worked this week?" Like
that, okay? So, that's the basic structure of these two tenses and as you can see, they
are quite different. Not only in how we construct them, but also as we learned earlier, when
we use them. Now, let's practice what you've learned. So,
I've written some sentences and questions on the board. Some of these are correct, and
some of them are incorrect, and you're going to help me decide which ones are right and
which ones are wrong. So, let's start with number one: I have visited
my sister yesterday. Is that right or wrong? It is actually wrong, but why is it wrong?
Think about it. So, it says, "I have visited", that's what tense? Present perfect. I have
visited my sister, but then it says, "yesterday". When is yesterday? Yesterday is a finished
time. So, if we keep the word "yesterday", then we cannot use present perfect, we have
to just use past simple. So, then we would say, "I visited my sister yesterday." Okay?
Now of course, in each of these, when it's wrong, we could probably change it either
way. We could make it into past simple or we could make it into present perfect, depending
on what we change, but I'll tell you which part we're going to keep so you can correct
it accordingly, alright? Next, number two: Did you see the doctor last
week? Is that right or wrong? That one is actually correct. Okay? Hope you chose that.
So here, we have, "Did you see", right? What tense is that? Past simple. So, "Did you see"
and it says "last week", so with past simple, can we use the finished time? Yes, definitely.
For sure, okay, so that one is just fine. Number three: Have you heard the news? Is
that right or wrong? Well, that one is also correct. "Have you heard", what tense is that?
Present perfect, right. And does it say when or anything? No, it doesn't. So, it just says,
"Have you heard the news?" "Yes, I have", "No, I haven't", okay? It's absolutely fine,
because we can use present perfect with no time expression, no time marker. It just means
in all the time until now and including now, have you heard? That's it. Number four: When have you sent the email?
Right or wrong? Tell me quickly, you know this one, okay? This is wrong! Why? Because
we have the critical word here, "when". As soon as you see "when", which tense should
you be using? Past simple. So, how do we fix this? "When did you send the email?" Okay?
As soon as you see "when", you know that it has to be in the past simple. So, then it
becomes, "When did you send the email?" Okay? Very good. ` Number five: I have applied for a job last
week. Right or wrong? This one is incorrect. Why? Because it says, "I have applied" and
that's what tense? Present perfect. But then it says, "last week". We can't do that, right?
Because "last week" is a finished time. So, let's change the sentence. Let's keep "last
week". If you want to say "last week", then you need to cancel this and just make a past
simple sentence. "I applied for a job last week." That's it, you're getting it, good.
And more important, you didn't memorize it, you understood it, and now you're applying
it. So, even if you write a sentence by mistake, you can look at it for a second and say, "Wait
a minute, okay", and you can fix your own sentences, not just these. But let's finish
doing these first. Number six: Our sales increased last year.
Right or wrong? That one is correct, okay? "Our sales increased", increased is what?
Past simple, and "last year" is a finished time, in past simple, we can definitely use
a finished time. Alright. Number seven: Have you watched the game last
night? Right or wrong? By now, you're getting really good at this and you know that this
is wrong, because we have here, "Have you watched", and here we have "last night". So,
this is present perfect, this is a finished time, and we can't use those together, right?
So, if we want to keep "last night", then we need to get rid of all this and turn it
into a past simple question. How do we do that? Instead of "Have you watched?", we say,
"Did you watch the game last night?" Very good, very good. Number eight: They have lived here for two
years. Right or wrong? Okay, so this one is actually correct. Why? Okay, "They have lived",
what tense? Present perfect. And here, we're just talking about how long they have lived
here, "for two years". It means they started two years ago and they still live here now,
which is what present perfect is all about, connects the past and the present. And very
often we use, remember, "for two years", "since 2018", whatever, okay? Excellent. Number nine: Did you train the team? Is that
correct? Yep! It is. Let's look at the last one for a second: Have you trained the team?
Is that correct? Hey, yes, it is! So, what's going on here? Kind of the same idea, but
in this case, we asked about it in what? The past simple. And here we used what? Present
perfect. So, can we do that? Yes, actually, sometimes, we can do that. Grammatically,
this sentence is correct, "Did you train the team?", it's fine. "Have you trained the team?",
that's fine because there's no past time expression or anything used. The meanings are almost
the same, but they're a little bit different. "Did you train the team?" is just like okay,
did you do that? Can I - I have a list of things to do and did you do that? Yes, I can
check it off my list, okay? It's done, it's finished. But, "Have you trained the team?",
you're really asking here, have you trained them, so are they ready now to do the new
things that we need them to do? So, the focus of this one is that if you have trained them,
and now they can do new things, okay? So, the focus is into the present, and here that
focus, "Did you train" is more - the focus is on the past. Alright? So, this was a very good review. I think you
did really well, because I think that you understood now what are the different points
you need to keep in mind when you're choosing between these two very popular tenses, alright?
And remember this, if you're in doubt and you're really not sure, make your life simpler
and use the simpler tense. So, use the past simple tense if you're not sure. Don't use
the present perfect tense if you're not sure. Okay? That's another little trick to keep
in mind. So, where do you go from here? As I said,
if you haven't watched the full lessons, then of course, you can go and watch those individual
lessons and understand each of these tenses very, very well. If you have watched the individual
lessons already, maybe you found that you're a little bit unsure and you want to go back
and review. Absolutely fine. This is your chance to get it all completely right and
not have to keep on wondering, okay, all your life, but really knowing what's right, okay?
And whenever you're ready, you can go on to the next tense in this series, which is the
present perfect continuous tense, alright? So, I wish you the very best with this. If
you'd like to practice this particular comparison a little bit more, you can also a quiz on
this on www.engvid.com . Thanks very much for watching, and all the best with your English.
