1. 确信,肯定：be cautious of 留心...,谨防... | be certain of 确信,肯定 | be certain to do sth 一定做...

2. 确信,深信：certain adj. 确定的,某一个;无疑的,必然的 | be certain of/确信,深信 | be certain to/必然;一定

3. 确信：be cautious to || 谨慎 | be certain of || 确信 | be certain to || 的确, 一定会

4. 确信,对...有把握：be central to 对...极为重要的 | be certain of 确信,对...有把握 | be characteristic of 为...所特有,是...的特征