which一词在科技英语中应用极为广泛,是科技英语中使用比较频繁的语法修饰成分,它的使用使句子变得更长更复杂。下面小编就来介绍下which修饰句子的用法。

　　只能使用which的情况:

　　1. 在“介词+关系代词”结构中，关系代词必须用which。如：

　　The house in which we live is very large. 我们住的房子非常大。 This is the reference book of which the teacher is speaking. 这就是老师正在谈及的那本参考书。

　　注意： 如果介词不放在修饰事物的限定性定语从句的句首， which就可换为that， 如：

　　This is the question which/that we’ve had so much discussion about. =This is the question about which we’ve had so much discussion. 这就是我们已经多次讨论过的问题。

　　2. 先行词为“those+表事物的复数名词”时， 关系代词通常只用which而不用that。如：

…… 此处隐藏1436字 ……

　　The only thing that we could do was to wait. 我们唯一能做的事就是等待。 注意：先行词被the same修饰时，关系代词也可用as。如：I need the same book that / as you have. 我需要有你一样的书。 6. 当先行词既包含人又包含物时。

　　如： They are talking of the heroines and their deeds that interest them. 他们正在谈论他们感兴趣的女英雄及她们的事迹。

　　7. 当先行词是疑问代词who，which，what或主句以这些词开头时。

　　如：Who that has ever worked together with him doesn’t admire him? 曾经和他一起工作过的谁不钦佩他?

　　Which is the star that is nearer to the earth? 哪个是离地球比较近的星星? 8. 当先行词为主句表语或关系代词为从句表语时。

　　如：That’s a good book that will help you a lot. 那是本对你很有帮助的书。 Our school is no longer the place that it used to be. 我们的学校现在已不是过去的那个样子了。

　　9. 先行词为time时，当time表示次数，引导词用that, 可省略。 当表示时间，可用that或when引导，都可省略。 如：I do remember the first time(that) I had ever heard the sweetest voice in the world.我很清楚地记得当我第一次听到世界上最美的声音的时候。 I did't remember the exact time (when/that) I arrived in Shanghai last month. 我不记得上个月到达上海的确切时间了。

　　10.在固定结构the same...that...; so...that...; such...that...以及it is/was...that...的强调句型中,须用that。如： This is the same museum that you once visited.