warned
have been warning
had warned
had been warning
Answer is Right!
Answer is Wrong!
The correct answer is: A. warned
The sentence is in the past simple tense, so the correct verb form should be the past simple of “warn”, which is “warned”.
The other options are incorrect because they are not in the past simple tense.
- “Have been warning” is in the present perfect continuous tense. This tense is used to talk about actions that started in the past and continue up to the present. In this case, the action of warning someone to keep away from certain people did not start in the past and continue up to the present. It is a single action that happened in the past.
- “Had warned” is in the past perfect tense. This tense is used to talk about actions that happened before another action in the past. In this case, the action of warning someone to keep away from certain people did not happen before the action of him not listening to you. They are both actions that happened in the past.
- “Had been warning” is in the past perfect continuous tense. This tense is used to talk about actions that started in the past, continued up to a point in the past, and then stopped. In this case, the action of warning someone to keep away from certain people did not start in the past, continue up to a point in the past, and then stop. It is a single action that happened in the past.