下列各句中，没有语病的一句是（ ）

___ I reit worked in all conditions ____ in water andextreme heat.

What are people supposed to do when they meet for the first time in China—They are supposed to _______.

It’s quite_____me why such things have been allowed to happen

There is no doubt ________ China has made a great breakthrough in developing education in thecountryside. [ ]