题目内容：

英语翻译
他谈起来就好象他什么都知道.
在所有这些任务中,这一项是最难的.
scientists assume that there is no life on the Mars.
i will make sure that every student has a copy of the book
the doctor performed an operatiom on him as soon as he was sent to the hospital
最后加一句哈.someone broke into my room and stole my computer last night.

优质解答

He talked up as if he knows everything.
In all of these tasks,this one is the most difficult.