SHOULD / SHOULDN'T + BARE INFINITIVE
A. Giving advice: should = it is the right thing to do
- You look tired. You should go to bed.
- The government should do more to help homeless people.
- If you want to lose weight, you shouldn't eat so much chocolate.
B. Something is not right or what we expect
- I wonder where Liz is. She should be here by now.
- The price on this packet is wrong. It should be £10 not £12.
C. We expect something to happen
- She's been studying hard for her exam so she should pass.
- There are plenty of hotels in this town. It shouldn't be difficult to find somewhere to stay.
D. if + should = feeling that the possibility is very small
- If the chocolates in this box should be damaged, please return to factory.
- If you should need my help, don't hesitate to let me know.
E. Should have done = you didn't do it but it would have been the right thing to do.
- It was a great party! You should have come.
- I feel sick. I shouldn't have eaten so many sweets.
F. Ought to = Should (advice)
- Do you think I ought to apply for this job?
- It was a great party. You ought to have come.
- Children ought to respect their elders.