问题

_____ ashes from the volcano in Iceland have caused problems for air traffic and business, scientists don’t think it will have long-term effects on human health

A:Since
B:As
C:While
D:Because

正确答案是：

同类题型

Why are many young children glasses now

Where did you learn Greek? —–I didn’t. I just sort of _____ when I lived there.

Pointing to the house on ____ roof grew lots of bush, the old man told me that was where I would stay.

Danny did all kinds of things to make the baby _________

Some researchers believe that there is no doubt ____ a cure for AIDS will be found.