In general, most tennis ________ on hard courts or on clay.

After the examination，my teacher told me that failure _______the mother of success.

— Is Tom still smoking? — No. By next Saturday he ＿＿ for a whole month without smoking a single cigarette.

The vegetables didn’t taste very good. They＿＿too long. 

 All flights ____ because of the snowstorm, many passengers could do nothing but take the train.