swear+doing还是to do?

题目

swear+doing还是to do?

答案

swear to do“郑重承诺,发誓要”.
She made him swear not to tell anyone.她让他发誓不会告诉任何人.
除此之外,swear to的后面还可以接名词,“断言,肯定,保证”.
I think I put the keys back in the drawer,but I couldn't swear to it.
我觉得我把钥匙放回抽屉里了,不过我不敢肯定.