M O D A L S

Modals : Can
(a)    I have some money. I can buy a book (b)   We have time and money. We can go to a movie (c)    Tom is strong. He can lift the heavy box	Can expresses ability and possibility
(d)   Correct : Yuko can speak English	The simple form of the main verb follows can. In (d) : speak is the main verb.
(e)    Incorrect : Yuko can to speak English	An infinitive with to does not follow can. In (e) : to speak is incorrect
(f)     Incorrect : Yuko can speaks English	A main verb following can does not have a final –s. in (f) : speaks is incorrect.
(g)   Alice can not come Alice cannot come Alice can’t come	Negative : Can + not = can not or cannot Contraction : Can + not = can’t
Question : Can + subject + main verb (h)   Can you speak Arabic? (i)     Can Rosa come to the party? (j)     Where can I buy a hammer? (k)   When can you help me?	Answer: Yes, I can / No, I can’t Yes, she can / No, she cannot At hardware store Tomorrow morning
Using could : Past of can
(l)     I am in Hawaii. I can go to the beach every time (m) I was in Hawaii last month. I could go to the beach every time when I was there	Could = the past form if can
(n)   I can’t go to the movie today. I have to study (o)   I couldn’t go to the movie last night. I had to study (p)   I could not go to the movie last night. I had to study	Negative : Could + not = couldn’t
(q)   Could you speak English before you came here?	Question : Could + subject + main verb

Modals : May / Might
(a)    It may rain tomorrow (b)   Anita may be at home now	May + verb (simple form) expresses a possibility in the future, as in (a) or a present possibility, as in (b)
(c)    It might rain tomorrow (d)   Anita might be at home now	Might has the sane meaning as may.
(e)    Ms. Lee may/might be at the meeting tomorrow	In (e) uses may/might to say, “I don’t know if Ms. Lee will be at the meeting, but it is possible.
(f)    Ms. Lee may/might not be at the meeting tomorrow	Negative form: may/might + not

Modals : be + able to
Present	(a)    I am able to touch my toes
Future	(b)   I will be able to go shopping tomorrow
Past	(c)    I wasn’t able to finish my homework last night

Modals : should
(a)    My clothes are dirty. I should wash them (b)   Tom is sleepy. He should go to bed (c)    You’re sick. You should see a doctor	Should means “this is a good idea”. This is good advice.
I – you – she – he – it – we – they à should + verb 1	Should is followed by the simple form of a verb.
(d)   You should not leave your book at home. You need it in class (e)    You shouldn’t leave your book at home.	Negative : should not Contractive : should + not = shouldn’t

Modals : Have + Infinitive (have to / has to)
(a)    People have to eat food (b)   Jack has to study for his test	Basically have the same meaning. Have + infinitive has a special meaning. It expresses the same idea as need.
(c)    I had to study last night	Past form : had + infinitive
(d)   Do you have to leave now? (e)    What time does Jim have to leave? (f)    Why did they have to leave yesterday?	Question : do, does or did is used in questions with have to.
(g)   I don’t have to study tonight (h)   The concert was free. We didn’t have to buy ticket.	Negative : don’t, doesn’t or didn’t is used with have to.

Modals : Must
(a)    People need food. People have to eat food (b)   People need food. People must eat food	(a)    and (b) have the same meaning
I – you – she – he – it – we – they à must	Must is followed by the simple form of a verb
(c)    You must not be late for work if you want to keep your job (d)    You don’t have to go the movie with us if you don’t want to	Must not = don’t do this! You don’t have to choice. Don’t have to = it’s not necessary, you have a  choice
Compare the following examples. Notice the different between must and should
Must Something is very important Something is necessary. You do not have a choice	Should Something is a good idea, but you have a choice
(e)    I must study tonight. I’m going to take a very important test tomorrow. (f)    You must take an English course. You cannot graduate without it. (g)   John, this is your mother speaking. You must eat your vegetables. You can’t leave the table until you eat your vegetables.	(h)   I should study tonight. I have some homework to do, but I’m tired. I’ll study tomorrow morning. I’m going to go to bed now. (i)     You should take an English course. It will help you. (j)     John, you should eat your vegetables. They’re good for you. You’ll grow up to be strong and healthy.

Polite questions : May I, Could I and Can I
(a)    May I borrow your pen? (b)   Could I borrow your pen? (c)    Can I borrow your pen?	They have the same meaning. I want to borrow your pen. I am asking politely to borrow your pen.
(d)   May I please borrow your pen? (e)    Could I please borrow your pen? (f)    Can I please borrow your pen?	Please is often used in polite question.
Typical responses : (g)   Yes, of courses (h)   Of course (i)     Certainly (j)     Sure (informal)* (k)   No problem (informal)*	Typical conversation : A: may I please borrow your pen? B: yes, of course. Here it is. A: thank you/ thanks

*informal English is typically used between friend and family members.

Polite questions : Could you and Would you
(a)    Could you please open the door? (b)   Would you please open the door?	They have the same meaning. I want you to open the door. I am asking you politely to open the door.
Typical responses : (c)    Yes, of courses (d)   I’d be glad to (e)    I’d be happy to (f)    Certainly (g)   Sure (informal)* (h)   No problem (informal)*	Typical conversation : A: Could you please open the door? B: I’d be glad to A: thank you/ thanks

Summary chart: Modal, Auxiliaries and Similar Expressions
Auxiliaries	Meaning	Example
can	ability	I can sing
	Polite question	Can you please help me?
could	Past ability	I couldn’t go to class yesterday
	Polite question	Could you please help me?
may	Possibility	It may rain tomorrow
	Polite question	May I help you?
might	Possibility	It might rain tomorrow
must	Necessity	You must have a passport
should	Advisability	You should see a doctor
will	Future happening	My sister will meet us at the airport
would	Polite question	Would you please open the door?
be able to	ability	I wasn’t able to attend the meeting
be going to	Future happening	Tina is going to meet us in the airport
have to / has to	necessity	I have to study tonight
had to	Past necessity	I had to study last night too