Henry speaks Chinese very well. He _________ in China since 2002

Manyexperts believe that teachers’ development is _______ the key to bettereducation lies

afraid that the branch might bendover and break, and he would be sent _____ to the ground.

sleep l6 to l8 hours in every 24hours, and they sleep less ________ they grow older.

On the National Day, up _____ into the air. Then the crowed cheered.