194 形式和用法（194 form and usage）.docVIP

194 形式和用法（194 form and usage） 194 form and usage A form The past participle is composed of Had completion of the past, so no person change: Affirmative: I, had / I, D, worked, etc. Negative: I, had, not / hadn, t, worked, etc. Question: had, I, worked? etc. Negative questions: had, I, not / hadn, t, I, worked? etc. B usage 1 the past perfect tense is the past tense equivalent to the present perfect tense. Present perfect： Ann, has, just, left.If, hurry, you, you, ll, catch, her. Ann just left. If you hurry, you can catch up with her. (see section 183rd.) Pluperfect： When, I, arrived, Ann, had, just, left. When I arrived, Ann had just left. Present perfect： I ve, lost, my, case. I lost my suitcase. (see section 184th.) Pluperfect： He, had, lost, his, case, and, had, borrow, Tom, to, s, pyjamas. He had lost his case and had to borrow Toms pajamas. However, the past perfect is not as limited as the present perfect tense, so it is only possible to express the action of unspecified time: He, had, left, his, case, on, the, 4, 40, train. He left his suitcase on the 4:40 train. 2 the present perfect tense can be used in conjunction with words such as since / for / always, indicating an action that begins in the past and continues or has just ended. (see section 186th.) Similarly, the past perfect tense can also be used to indicate the action that has been started before a certain moment in the past: (a) continuing at that time; or (b) stop or just stop at that time. It should be noted, however, that the past perfect tense can also be used to express: (c) the act of stopping at some point prior to the said moment. (a), (b), (c) these three types of examples are listed below: (a) Bill, was, in, uniform, I, met, him.He, had, a, soldier, for, tenyears / since, he, was, seventeen, and, planned, to, been, stay, in,, the, army, when, till, hewas, thirty. When I met Bill, he was wearing a military uniform. At that time he had been a soldier for ten years He has been a soldier since