时态的呼应 , V+ Z9 w M) h4 j5 f" `6 x 时态的呼应又称时态一致(Sequence of Tenses),指的是某些从句里的动词谓语时态必须和主句里的时态保持一致。 , B8 A9 A# Y/ m 如果主句里的谓语动词是过去时态(过去时或过去完成时),那么从句的谓语动词时态也相应地要用过去时。时态的呼应主要发生在间接引语和宾语从句中,但其他从句有时也存在时态一致的问题。 " M* Q+ t. J0 S; T
--He explained that he had learned Chinese for many years.(现在完成时变为过去完成时) 9 e8 \( O! Q; L --He said he had been collecting materials on that subject for a long time.(过去进行时变为过去完成进行时) www.examw.com" w) N7 c: \& }$ v2 f8 r9 c/ k
--He told me that they would have completed that project by the end of the year.(将来完成时变为过去将来完成时) 4 @6 }. i, J: T$ m/ g* u/ V+ O; i
虽然主句用了过去时等,如果从句表示的是科学真理、客观事实或某人(物)的经常性特点时,其时态可以不必遵守时态呼应的规则而仍用一般现在时。 0 W" }0 W7 t+ g
--Galileo proved that the earth revolves round the sun. . l4 |* G9 C/ ] v6 f
--The teacher told the students that knowledge is power. 9 v9 H) c' b& |2 ]
如果从句中有一个表示绝对过去时间的状语,就不必把一般过去时变为过去完成时。 3 s& {7 n2 J/ j3 }; }+ E --He said that he joined the Red Army in 1933.