An explosion is a sudden increase in amount（）

She is very nice, but because she has a（）way of speaking, she is slow in making friends

Our department（）courses in several foreign languages.

Nobody knows how long and how seriously the shakiness（不穩(wěn)定） of big businesses will （） down the economy.

I don't know who on（）stole the diamond last night.

His company promised to pay for his health （）in addition to other benefits.

He never（）to read the news but turned at once to the crossword puzzle on the last page.

The price they offered for my old car was so low that I（）it down.

The aircraft vanished without（）

I was（）than angry when I saw how they'd ruined the landscape.