35．The highest award was given to Anna, who_________so hard on the project for years, and at last her efforts paid off

下列句子中，没有语病的一项是（ ）

I think this is the most interesting thing _____has happened to us .

s world is changing rapidly, making_____ necessary for us to continue learning otherwise we can’t keep up with thetime.

The thieves ______ the waste paper all over the room while they were searching for the diamond ting.