be sure 和make sure 的區別：

Ⅰ. be sure 指某人對某事或對某種情況有把握，常譯為：“確信”；

make sure 指“務必、務請、確保”將某事弄清楚。如：

① I am sure that he is honest. 我相信他是誠實的。

② I have made sure that he is honest. 我已瞭解清楚他是誠實的。

Ⅱ. 二者後面均可接of 或about 引出的短語。如：

① I am sure of success

= I am sure that I will succeed. 我深信會成功。

② Will you make sure of his return?

= Will you make sure that he returned? 請你查明他是否真的回來了。好嗎？

Ⅲ. make sure 後面的that 從句一般不用或很少用將來時；

be sure 後面的that從句則可用將來時。如：

① Make sure that you come here before five. 你一定要在5點前來。

② I am sure that he will come. 我相信他一定會來的。

Ⅳ. 兩者後面接不定式，均表示“一定要做某事”，但make sure 通常只用於祈使句；

而be sure 則不受限制。如：

① Make sure to come to party on time. 一定要準時來參加晚會。

② He is sure to call you up. 他準會給你打電話的。