Common errors in the use of tenses

Here the error lies in using the present continuous instead of the present perfect continuous. We use the present perfect continuous tense to talk about an action which started in the past, has gone on till the present and is still continuing.

• Incorrect: I have seen him yesterday.
• Correct: I saw him yesterday.
• Incorrect: He has returned from London last week.
• Correct: He returned from London last week.

Here the error lies in using the present perfect tense instead of the simple past tense. The present perfect is a present tense. It can’t be used with adverbs of past time.

• Incorrect: See that you will not do any damage.
• Correct: See that you do not do any damage.

It is wrong to use the future tense in the subordinate clause when the verb in the main clause is in the imperative mood.

• Incorrect: I will call you when the dinner will be ready.
• Correct: I will call you when the dinner is ready.
• Incorrect: He will help if you will ask him.
• Correct: He will help if you ask him.

When the verb in the main clause is in the future tense, the verb in the subordinate clause should be in the present and not in the future.