1.before: …before I could say a word./It may be some time before the situation improves
How long it'll be before I can go back to work?
2.when: It was six o'clock when they arrived at the hotel.
3.since: It's three years since I smoked.
4.as: Great as the difficulty was,.../Much as I admire,...
5.where: They notice that plants don't grow well where there is much shade.
My doctor advised me to live where the air is fresher.
I can when my headache disappear thoroughly.
If you go, so will I.
have been painting all day/be always doing/I did lock it/will still be sleeping/will have left
The papers are still being corrected/It is being served in the dining room.
比如，couldn't have done/might have done/needn't have done/should/ought to have done
No student shall go out of school without the teacher's permission.
Tell him that he shall have the wonderful book tomorrow afternoon.
It is the rule that every driver shall obey in this city.
Shall I/he book a table?
must : If you must know her name, her name is Mabel.
would: When I was young, I would sit under the old tree listening to grandpa tell me stories.
should: It's strange that Tom, the most excellent student in our grade should fail in the exam.
may: May you succeed!/May you be happy!
比如：Just in case!/Take your time!/Take it easy!/You can't be serious/Up to you!/What if?/Can you make it?/What for?/What kept you?/Of what?/Exactly!/With pleasure!/That isn't due yet./The early train is due to leave at 5:30 a.m./I'll give you a lift./Why not?/You are wanted on the phone.
She went to the market, bought some bananas and visited her cousin.
She said, and turning away from him, walked rapidly away.
Go straight ahead, and you will see a hotel in front of you.