2016年托福考试介词专项辅导一

　　1. between/among，between不一定只是两者之间，among 一定是两者以上

　　The distance/reaction between the stars/trees. 两两之间

　　among the two separate realms.领域 ×

　　2. in/for/since (与时态有关)

　　(1) in + 时刻点 eg: in 1979 用于一般过去时

　　in+一段时间 eg: in recent years 用于完成时态, in two days 用于将来时态

　　(2) for 作爲conj. “因为”，引导塬因状语从句，并列连词,不能位于句首只能位于句中

　　for 作爲prep. for+ 一段时间 for three years 可用于各种过去时态或完成时态

　　例题：

　　Adella Prentiss Hrghes (served) (as) (manager) of the Cleveland Orchestra (since) fifteen years.

　　答案: D sinceàfor

　　(3) since 作爲conj., “因为”“自从”， 引导塬因状语从句，句首居多，Since +句子，句子。等于because

　　作爲prep., “自从”+时刻点， eg: since 1949 用于完成时态(“自从”+句子，出现较少)

　　作爲adv. A. 与完成时连用，表示过去某个时间某个事件到现在 since have done

　　B. 与过去时连用时 = ago

　　例题：

　　50. Tom was elected (president) last semester, (but) he (since has devoted) (few) of his time to his job.

　　答案: D fewàlittle

　　51. The (oldest) public edifice in Washington D.C., the White House was (originally) constructed in the 1790’s, (also) has been rebuilt or extensively remodeled (three times since).

　　答案: C alsoàand

　　52. Eleanor Roosevelt (set) the standard against which the (wives) of (all) United States Presidents since have (evaluated).

　　答案: D evaluatedàbeen evaluated