The threats to the health of astronauts in space are very different from ______ on earth.

He has learned         , no matter what happens and how bad      seems today, life goes on and it will be better tomorrow.

Naturally I will come to you for advice whenever I feel I need             

Would you like tea or coffee?
--_____, thank you. I’ve just had some water.

More than 100 students have entered for the competition and________ gains the most points will be the winner.

—When shall we go for an outing?
—It's up to you. Make it  time you like.

How would you like     if you didn't see me for two or three days?

The population of China is larger than ______ of the United States.

I’m moving to the countryside because the air there is much fresher
than      in the city.

_____ do you think will teach us maths next term？