1 confident that you know something or that something is true or correct 确信的,有把握的; not before noun
不用于名词前
CERTAIN YOU KNOW STH
确信自己知道某事
我不太清楚这个音我发得对不对。
2 a. to find out if something is true or to check that something has been done b. to do something so that you can be certain of the result 设法确保
make sure