It is necessary to know the difference between the two tenses, since the misuse of tenses leads to a certain class of errors.
73. Sequence of Infinitive Tenses. The wrong tense of the infinitive is frequently used. The following rules should be observed:
1. If the action referred to by the infinitive is of the same time or of later time than that indicated by the predicate verb, the present infinitive should be used.
2. When the action referred to by the infinitive is regarded as completed at the time indicated by the predicate verb, the perfect infinitive should be used.
Examine the following examples:
| Wrong: I should have liked to have gone. |
| Right: I should have liked to go (same or later time). |
| Right: I should like to have gone (earlier time). |
| Wrong: It was bad to have been discovered. |
| Right: It is bad to have been discovered (earlier time). |
| Right: It was bad to be discovered (same or later time). |
| Right: She did not believe her son to have committed the crime (earlier time). |
| Right: When he died, he believed himself to have been defeated for the office (earlier time.) |
Exercise 54
In the following sentences choose the proper form from those italicized: