表示选择的并列结构

　　1) or　意思为"否则"。

　　I must work hard, or I'll fail¹ in the exam².

　　2) either³…or　意思为"或者……或者……"。注意谓语动词采用就近原则。

　　Either you or I am right.

1 fail   

v.失败，不及格，辜负，缺少

参考例句：

• If I should fail I would try again.万一失败，我还要试一试。
• If you fail now,who will pick up the pieces?你现在要是失败了，谁来收拾残局？

2 exam   

n.(=examination)检查；考试

参考例句：

• I hope to pass this exam.我希望通过这次考试。
• His exam results were good.他的测验成绩不错。

3 either   

adj.任一，两方的；prep.任一，随便任一个；conj.或，也

参考例句：

• I have bought two books,you can have either.我买了两本书，你要哪一本都可以。
• I don't think either of them are at home.我想他们中任何一个都不在家。