It's five o'clock.
Would you like a cup of tea?
All the auxiliary verbs except be, do and have are called modals.
Unlike other auxiliary verbs modals only exist in their helping form; they cannot act alone as the main verb in a sentence.
Be, do, and have also differ from the other auxiliaries in that they can also serve as ordinary verbs in a given sentence.
The modal verbs are all those that we have described in the last posts:
CAN, COULD, MAY, MIGHT, MUST, SHALL, SHOULD, OUGHT TO, WILL and WOULD
Modals are commonly used for asking permission
examples:
- Can I ask you an information?
- May I have a cup of tea? (may is always more formal)
- Could I open the window?
we use can or could to ask people to do something:
- Can you wait a moment please?
- Could you wait a moment please?
- Dave, can you do me a favor?
Asking for things:
- Can I have this magazine please? (in a shop)
- Could you pass me the oil please? (during a meal)
- May I have this book please?
Asking to do things:
- Hello, can I speak to Laura please? (on the phone)
- Could I use your phone for a moment please?
- May I come in?
Offering to do things:
- Can I get you a glass of water?
- Can I help you?
Offering and inviting:
- Would you like a cup of tea?
- Would you like to come for lunch on Sunday?
- I'd like to book a room, please.


