Betty, could you answer my question— Sorry, Mr. Green. I didn’t hear you. I _______about something else.

Hi， Ann. How can you improve your English so much— Oh， nothing difficult. The _____ you work at it， the _____ progress you will make.

Giving a hand to others _____ little, but it’ll bring you _____ much.

Stop! You can never touch this machine when it ________, it is very dangerous

George once told me that he would visit our house，but，for various reasons，he________so far