24) Since + 主语 + 过去式，主语 + 现在完成式
例如：Since he went to senior high school， he has worked very hard.自从他上高中，他一直很用功。
25) An advantage of… is that + 句子 (……的优点是……)
例如：An advantage of using the solar energy is that it won't create (produce) any pollution. 使用太阳能的优点是它不会制造任何污染。
26) It was not until recently that….( 直到最近, ……)
例如：It was not until recently that the problem was solved. 直到最近这个问题才被解决。
27) We will be successful as long as we…. (只要我们……，我们就会成功的)
例如：We will be successful as long as we insist on working hard.只要我们坚持努力工作，我们会成功的。
28) No matter + wh-从句，…
例如：No matter how difficult English may be, you should do your best to learn it.不管英语有多么难，你都应该尽你最大的努力来学它。
注意：此句型一般可以改为疑问词+ever引导的从句，+主句
例如：Whatever he asks you to do, please refuse him.无论他让你做什么，都请拒绝他。
29) It's useless/ no good / no use doing sth. (做……是没有用的)
例如：It's no use crying over spilt milk. 覆水难收。
30) The reason why + 从句 is that + 从句 (……的原因是……)
例如：The reason why we have to grow trees is that they can supply fresh air for us.我们必须种树的原因是它们能供应我们新鲜的空气。