I am not sure ( )there are living things on other plants or not.Even scientists are not sure.A.if B.that C.whether D.where为什么不可以选A有什么结构吗?

I am not sure是什么意思 Er...i am not sure. I am not sure who will be the man. I am not sure I am in the end is not like you1 I am not sure who that book belongs to还是I am not sure whom the book belongs to I'm sure I am not wrong i am not sure反义疑问句 I am not sure what your talking 翻译成中文：I am not sure i am not sure 什么意思 I am not sure同义句 maybe.but I am not sure. Sure.I am not a bad I AM NOT SURE YET?什么意思? I am not sure.that I am gay what the meaning ofI'm not sure I am up for this I though about going to the _____ but I am not sure. am,the,I,sorry,sure,not,about,way,zoo,the,to