1 专四必备语法 一 、时态、语态 时态、语态需要掌握的要点： 1 .表达将来时的形式： (1)在 时 间 、条件、让步从句中，一般现在 时 代替将来时 ，但要注意区别从句的类型，如：I’ll tell him when you will ring again. 我告诉他你什么时 候再来电话。(宾语从句) 比较：I’ll tell him when you ring again.你再打电话时 我告诉他。(状语从句) (2)在 make sure, make certain, see (to it) 后的 that 从句中，谓语动词用一般现在 时 代替将来时 ，如：See to it that you include in the paper whatever questions they didn’t know the answer to last time.(include 不能用 will include 或其他形式) 2 .完成时是时态测试的重点，注意与完成时连用的句型和时间状语： (1)by/between/up to/till +过去时 间 、since、by the time/when +表示过去发生情况的从句，主句用过去完成时 。 如：We had just had our breakfast when an old man came to the door. Between 1897 and 1919 at least 29 motion pictures in which artificial beings were portrayed had been produced.(表示 1919 年时 已发生的情况) (2)by +将来时 间 、by the time/ when +谓语动词是一般现在 时 的从句，主句用将来完成时 。如：By the time you arrive in London, we will have stayed in Europe for two weeks. I hope her health will have improved greatly by the time we come back next year. (3)by now 、 since + 过 去 时 间 、 in/during/for/over/the past/last few( 或 具 体 数字)years/days/months，主句用现在 完成时 ,如： The changes that had taken place in air travel during the last sixty years would have seemed completely impossible to even the most brilliant scientists at the turn of the 19th century.但在 it is +具体时 间 since/before 这一句型中，主句更多的时 候不用完成时 。 It is four years since John left school. (4)在 It is the +序数词/形容词最高级+that 的定语从句中，谓语动词常用现在 完成时 。如： It isn’t the first time that I have found myse...
