STEP 1Choose the correct option
STEP 2Add exercises you like to Favourites
If we are speaking of an action just finished, we must use the present perfect instead of the simple past tense. For example, immediately after the clock strikes, we shouldn't say The clock struck, but The clock has struck.
As a rule, verbs denoting a state rather than an act have no continuous forms, like understand, know, believe, like, love, belong, prefer, consist, mean, hear, see, etc.
Use the present tense in a future conditional in the if clause and the future tense in the main clause
But the future tense may be used in an if clause expressing a request: If you will/'ll give me some money I will/'ll buy you a drink.
If you begin with a verb referring to past time, keep the verb forms in the past. The same rule applies to tenses throughout a composition.
Don't use must and ought to as past tenses. To express a past duty (which wasn't done) use the perfect infinitive without to after ought to or should, or expressions such as had to, was obliged to.
In indirect speech use must and ought to as past tenses: He said he must do it.