比较while, when, as 1）as, when 引导短暂性动作的动词。 Just as / Just when / When I stopped my car, a man came up to me. 2）当从句的动作发生于主句动作之前，只能用when 引导这个从句，不可用as 或 while
让步状语从句 1）though, although 注意：当有though, although时，后面的从句不能有but，但是 though 和yet可连用 Although it s raining, they are still working in the field. 虽然在下雨，但他们仍在地里干活
目的状语从句 表示目的状语的从句可以由that, so that, in order that, lest, for fear that, in case等词引导，例如： You must speak louder so that /in order that you can be heard by all. He wrote the name
与后接名词或代词保持一致 1） 用half of, part of, most of, a portion of 等词引起主语时，动词通常与of后面的名词，代词保持一致。 Most of his money is spent on books. Most of the students are taking an a
谓语需用单数 1） 代词each和由every, some, no, any等构成的复合代词作主语，或主语中含有each, every, 谓语需用单数。 Each of us has a tape-recorder. There is something wrong with my watch. 2） 当主语是一
谓语动词与前面的主语一致 当主语后面跟有with, together with, like, except, but, no less than, as well as 等词引起的短语时，谓语动词与前面的主语一致。 The teacher together with some students is visitin
主谓一致中的靠近原则 1）当there be 句型的主语是一系列事物时，谓语应与最邻近的主语保持一致。 There is a pen, a knife and several books on the desk.. There are twenty boy-students and twenty-three girl
时态一致 1) 如果从句所叙述的为真理或不变的事实，则永远用现在时。 At that time, people did not know that the earth moves. He told me last week that he is eighteen. 2) 宾语从句中的助动词ought, need, mu
一般现在时代替将来时 （1）时间状语从句，条件句中，从句用一般现在时代替将来时 When, while, before, after, till, once, as soon as, so long as, by the time, if, in case (that), unless, even if, whether,
不用进行时的动词 1) 事实状态的动词 have, belong, possess, cost, owe, exist, include, contain, matter, weigh, measure, continue I have two brothers. This house belongs to my sister. 2) 心理状态的动词
比较since和for Since 用来说明动作起始时间，for用来说明动作延续时间长度。 I have lived here for more than twenty years. I have lived here since I was born.. My aunt has worked in a clinic since 1949.
用于现在完成时的句型 1）It is the first / second time . that 结构中的从句部分，用现在完成时。 It is the first time that I have visited the city. 这是我第一次访问这座城市。 It was the third time that
一般现在时表将来 1）下列动词：come, go, arrive, leave, start, begin, return的一般现在时表将来。这主要用来表示在时间上已确定或安排好的事情。 The train leaves at six tomorrow morning. When does the bus
be going to / will 用于条件句时， be going to 表将来 will 表意愿 If you are going to make a journey, you d better get ready for it as soon as possible. Now if you will take off your clothes, we will
一般将来时 1) shall用于第一人称，常被will 所代替。 will 在陈述句中用于各人称，在争求意见时常用于第二人称。 Which paragraph shall I read first. Will you be at home at seven this evening? 2) be going
used to / be used to used to + do： 过去常常 表示过去习惯性的动作或状态，但如今已不存在。 Mother used not to be so forgetful. Scarf used to take a walk.(过去常常散步) be used to + doing：对 已感到习
反意疑问句 1)陈述部分的主语是I，疑问部分要用 aren t I. I m as tall as your sister，aren t I? 2)陈述部分的谓语是wish，疑问部分要用may +主语。 I wish to have a word with you, may I? 3)陈述部分用 no, no
