| 词组 | ago |
| 释义 | 1．一般说来，用了 ago 不可用完成时态，如可以说 She saw him a week ago，不可说 She has seen him a week ago。但用了助动词或用在分词、动名词或不定式的形式里便可以用完成时态。例如： She must have seen him a week ago. She may have seen him a week ago. She cannot have seen him a week ago. Having seen him a week ago, she is always thinking of him. She speaks of having seen him a week ago. She seems to have seen him a week ago. 即使不用助动词，也不用在分词、动名词或不定式的形式里，偶尔也有用完成时态而用 ago 的。例如：I have long ago given up that habit. 这里语气重在“早已……”。 2．说现在的多少时间以前，该用 ago，如 He started five minutes ago 和 He returned home twenty years ago。说过去某时的多少时间以前，该用 before，如 He told me he had seen her a few minutes before。不过英美也有人用 ago 的，往往用 ago 语气比较生动。说将来某时的多少时间以前，也该用 before。例如：When you call at the shop again this afternoon, you may be told that the book has been sold only a few minutes before. 说任何某时（不是现在、过去或将来的某时）的多少时间以前，也该用 before。例如：He often forgets what he has heard only a few minutes before. （这三种场合里的 before 改作 previously 或 earlier 也可以，但不及 before 普通。） 3．It is five years ago that he returned home 和 It was five years ago that he returned home 都可以说。用 is 着重“到现在已有 5 年”的意思，假使在 ago 后面加上 now，这意思更明显。不可说 It was five years ago now that he returned home。 4．as long ago as 1864 等表达方式里在第二个 as 后面没有 in。可以说 as long as forty years ago，不可说 as long ago as forty years。 5．She died three years ago next Monday 是“她在下一个星期一的 3 年以前死去”。假定下一个星期一是 8 月 5 日，那末她便是 3 年前的 8 月 5 日死的。It happened a fortnight ago tomorrow 是“这件事发生在 13 天以前。” 6．“最近过去的第二个晚上”习惯说 two evenings ago，说“最近过去的第三个夏天”习惯说 three summers ago。 |
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