14/09/2022
Should is usually followed by an infinitive without ‘to’: You should eat more fresh fruit. Sometimes should is used without a following infinitive: I don’t always do everything I should.
Should does not change its form, so the third person singular form does not end in ‘-s’: She should see a doctor about that cough.
Questions and negatives are formed without ‘do’: Should we come back later?You should not bring up embarrassing topics.
The negative form not is often shortened in conversation or informal writing to shouldn’t: Those kids shouldn’t be in there.
Should is often used in question tags: We should leave a tip, ’t we?
has no participles and no infinitive form.
There is no past tense, but should have been followed by a past participle that can be used for referring to actions that did not happen or for actions that have probably happened: I have brought an umbrella (=I did not bring one).The meeting should have finished by now (=it is likely it has ended).
When indirect speech is introduced by a verb in the past tense, can be used as the past tense of shall: I explained that I should be too busy to see them the following day.
sourse - https://www.macmillandictionary.com/dictionary/british/should
