Children under sixteen are not permitted to participate in such kind of activities _____ bad for their mental development.

How long do you think it will be _______ scientists succeed in providing a cure for cancer?

Two more people in Shanghai have been ________ to be infected with the deadly H7N9 bird flu, local authorities said on Sunday.

I was angry _______ him for keeping us waiting.[ ]

Which team will the Chinese football team play _____? —The Korean team. [ ]