(1)be certain(sure) to do sth.“确定会做……”（表示某事将要发生）。如：
He is certain(sure) to come next Sunday.
(2)be certain(sure) of/ about sth.“确信、有把握”（表示某个人的思想状态）。如：
We are certain/ sure of victory.
(3)名词从句作主语时，一般多用certain.
It is certain that he will come.
2、be different from 与……不同
Your idea is different from mine. 你的想法和我的不同。
比照：make sb./ sth. different from使某人/某物不同于……
Her special accent makes her different from others. 她特别的口音使她与众不同。
3、be familiar with/be familiar to
be familiar with的主语是有生命的事，意为“某人对人、事熟识”；be familiar to 的主语是无生命的事物，意为“某人/事为某人所熟识”，比照:He is very familiar with the names of plants in 。Suzhou and Hangzhou are familiar to many foreigne
