You must watch this lesson. You just have to
watch this lesson. It's really important, because it'll
help you, and it's confusing in English. Actually, you don't have to watch this lesson,
if you don't want to; it's your choice, but you've already clicked on
it, so let's continue. I'm going to explain to you two modal verbs
that are really confusing in English because the positive and the negative
have different meanings. Let's start with the first
one and the easiest one. You guys have learned this, I'm sure before,
if you studied grammar; or if you haven't studied grammar, you guys maybe
have even heard about this. It's confusing. So, what I'm going to teach you today is the
difference between the modals: "must" and "have to". In the positive, "must" and "have to" have the
exact same meaning or the exact same function. When we use this grammar... It's grammar. When we use this grammar, "must" you can
think about it like a law or a rule. Okay? Something that is very, very, very important;
basically, if you don't do it, there will be bad things that will happen. So: "must" and "have to" we both
use for very strong rules or laws. So, I want you to think
about in your daily life. Or I'll give you an
example of travelling. So you're going to get on an
airplane, so you go to the airport. What are some things you must
have to get on the airplane? One, you must have-or you have
to have-an airplane ticket. If you don't have an airplane ticket, you're
not going to get on that airplane, so you buy one. The second thing that you must have-or you
have to have-is a passport or some kind of legal ID; depending on where
you are travelling to. If you're flying internationally to a different
country, you definitely have to have-or must have-a passport. It's important to have money. You must have some money, or
you have to have some money. How are you going to live? How are you...? You got money. Okay. So: "must" and "have to" in the
positive form are exactly the same. I don't care what anyone else has told you
before; I don't care what your grammar books tell you; I don't care what your mom tells
you - "must" and "have to" in the positive are completely equal. We don't make a difference. You have to do this or you must
do this - the ending is the same. It's a rule or a law; if you don't do it,
there's going to be some problems or you just won't be accepted. Can you think of an example in your life that
you have rule or a law that you must or have to do? Good. Okay. Let's look at also the
grammar of "have to". So, "must" is very easy. It's going to be subject plus
"must" plus your base verb. This is called a modal
verb, which is "must". So, for example: Subject plus
"must" plus your base verb. "I must have a ticket to
get on that airplane." If I don't have a ticket, I
can't get on the airplane. But when we use "have to", we have to be very,
very careful or we must be careful with our subject and our verb agreement. So, if you have: "He", "She" or "It", we have
to say: "has to"; but if you use: "I", "We", "They", or "You", we have to
say or we must say: "have to". So: "It has to be great.", "We have
to go now; it's very important." So, be careful with our grammar. The "must" one is easier. So, if you're deciding on which one you like
better - choose "must" because you don't have to worry about the subject
and the verb agreement. But again, they are
not different. "Must" and "have to"
are exactly the same. The structure is different, but the function
or the way we use it is exactly the same. You choose which one
you like the most. The negative of "must not" is basically
telling us a rule in the negative. For example, you can say: "On the
airplane, you must not smoke." This is a very, very strict law or rule on any
airplane in any country of the world that smoking is prohibited;
you can't do it. If you do it, you will get arrested
which means you'll go to jail. I don't know if you go to jail, but definitely
the police will come and you have to pay a lot of money, so don't do it. "Must not" we can
shorten to: "mustn't". You mustn't cough during recording
because it makes a loud noise. But when we say this, the "t" is
silent; we do not say: "mustn't". You mustn't pronounce the "t". You... When we do this, the "t" is
actually silent, we say... So, we say: "musn't". So, I can say: "You mustn't smoke on an airplane",
or: "You must not smoke on the airplane." Again, they're the same. "Mustn't", faster and sounds more natural, but
if you want to say: "must not", it sounds even stronger. So, if you really want to enforce something
or tell someone strongly: "Oh, you must not do that! That's bad! Bad, kitten!" Is there a kitten? Where's a kitten? So: "must not" has the
same function as "must". You're talking about a very
strong rule or a very strong law. Now, this is where we get really confused
because the negative of "have to", if you guys look at this, is: "doesn't have to" with:
"He", "She", "It"; and "don't have to" with: "I", "You", "We", and "They". So, rule number one: When you have "have to" you
have to be careful-or you must be careful-of the function and of the structure,
because the structure is crazy. If you use negative, we do not change the verb
here; we use the auxiliary verb "doesn't" and "don't", but
you keep the verb. You cannot say; you must not say because
it's a rule: "She/He/It doesn't has". "Doesn't has" is wrong. You have to use:
"doesn't have to". Okay? So be very careful
with these ones. "Doesn't" and "don't" are the verbs that
are going to change in this grammar. So confusing; just use this one. But, again, as I told you,
the function is different. Okay? Also, remember: Every time you learn new grammar
or you learn a new thing in English, please try and think about:
"What's the function? Why do I have to learn
this stupid grammar point? How can I use this
in real life?" That's what you should always be asking yourself
in your classroom, if you're studying by yourself, if you're speaking, go: "Why? Why? Why? Why? Why? Why don't I say: 'She doesn't
have to smoke on the airplane'? Why can't I say that?" The difference is: This kind of grammar,
it's very different from a rule or a law. This kind of... Drama. This kind of grammar, it's basically-and
this is fun-it's your choice. Oh. It's your option. If you want to, you can;
but you don't have to. So you have the option
to do something. Oops. Another thing that you will understand from
this is that people will give you their opinion or their advice; and when we give someone's
opinion or advice, they're also going to use this structure. So, this one is a very strong rule or law;
this one is not a strong rule or a law - this is your choice or your option, or
usually someone's opinion or advice. So, let's say that you're getting ready
to travel and your mom says: "Hey. You don't have to call me
every day", but you should. Or your friend says: "You know, it's okay; you
don't have to buy me a souvenir or a gift when you go to this new country",
but I'd like it a lot. This is someone's opinion. You don't have to do it; nobody's holding a
gun to your head, saying: "Buy your friend a gift in this over-priced souvenir
store", and your mother... Mom, thanks for all the advice. Advice is something that, again, is someone's
opinion; it's never a law, unless it's from your mom. I'm joking. Advice and opinion are the same,
so it's what people recommend. But you have to understand that if you
don't want to, you don't have to. When you get on that airplane, there
are some rules that you must follow. You must do up your seatbelt. Okay? This is a rule and a law. You must turn off
your cellphone. But when the food comes down the aisle and you
go: "Wow, that smells great", guess what? You do not have to eat that
terrible airplane food. It's your choice. If you want to, you can eat that chicken
or beef; but she doesn't have to. She doesn't have to eat it, if she
doesn't want to; it's her choice. When you go to the airport and
you're shopping - hey, guess what? You don't have to buy that
bag; it's not important. But you want to, so
that's your choice. "Oh, I want to buy the bag!" But you don't have
to; it's not a rule. When you... If you come to Canada, you don't
have to drink maple syrup. Well, we don't drink it. You don't have to
try maple syrup. Hey, if you don't want to try
maple syrup, that's your choice. You don't have to do it,
but you should; it's fun. I want you to think about things that you have
encountered - maybe at your work or maybe when you're travelling, or anytime in your
life, maybe at your house - things that you have made a choice to not do; things that
your mother tells you that you don't have to do, but you should. You don't have to donate money, but
you should; it's a great idea. You must follow me on YouTube. You must not write bad things. You have to continue
learning English. Hey, but guess what? You don't have to, if you don't want
to; it's your choice; it's my opinion. Until then, bye-bye.
