Would you like to stay ____ days in Beijing—No, thanks. I’m afraid I’ll be back tomorrow.

She is ________ new comer to ________physics but she has made some useful inventions already

Do you know that Yuan Longping is known as ______father of hybrid rice

When I passed the park I saw the grass______by some workers with lawn movers

Oh，Mum，I simply like my new bike.—Look after it________ it will last long.