People often want their life to go perfectly, but accept the         that nothing on the earth is flawless.

In recent years travel agencies have succeeded in selling us the idea that ________, the better our holidays will be. 

_____ is a good form of exercise for both young and old.

It is said that dogs will keep you______for a8 long as you want when you are feeling lonely。

 There existed an obvious________ between the accounts of the witnesses, so a judgment was not announced in court.