The correct answer is "since". The phrase It has been years since I last saw him uses since to indicate the point in time when the action last occurred.

The correct answer is "has worked". The phrase since 2020 requires the present perfect tense has worked.

The correct answer is "so". The structure so plus adjective plus that expresses cause and effect. It is so cold that we cannot swim.

The correct answer is "haven't been". The phrase since 2019 requires the present perfect tense. I haven't been to Paris since 2019.

The correct answer is "as good". The structure as good as is used for comparisons of equality. No other student is as good as her.

The correct answer is "able". The phrase is not able to drive expresses inability. He is not able to drive.

The correct answer is "had not told". After I wish, the past perfect tense had not told expresses regret about a past action.

The correct answer is "did not need to". Did not need to expresses that something was unnecessary in the past.

The correct answer is "drink". After would rather, the base form of the verb is used. I would rather drink coffee than tea.

The correct answer is "been learning". The present perfect continuous tense has been learning emphasizes the duration of the action that started in the past and continues to the present.

The correct answer is "old enough". The structure too young to vote is transformed to not old enough to vote.

The correct answer is "was finished". The active voice finished becomes passive voice was finished in the past simple tense.

The correct answer is "had". After I wish, the past simple tense is used to express a wish about the present. I wish I had more money.

The correct answer is "failed to go". Failed to go means did not manage to go, expressing lack of success.

The correct answer is "since". It has been a week since he last called me uses since to indicate the point in time when the action last occurred.

The correct answer is "of". In spite of is the correct prepositional phrase. In spite of the rain, we went out.

The correct answer is "unable". Was unable to pass means did not have the ability to pass.

The correct answer is "to". The verb promised is followed by an infinitive with to. She promised to help.

The correct answer is "by". The correct preposition after surprised when indicating the cause is by. I was surprised by his victory.

The correct answer is "may". May have forgotten expresses possibility about a past action.