While playing ping-pong, our eyes see the ball coming, judge its speed and then hit it back ________ it should go.
| A．when | B．why | C．what | D．where |
19．Mrs．Brown is so_________about her housework that few servants Want to work for her．
| A．skillful | B．neat | C．particular | D．Special |
18．After you have used the dictionary，please just put it back_________it belongs．
| A．to whom | B．to which | C．what | D．Where |
17．Now, boys，I’ll_________the story where I stopped yesterday．
| A．take over | B．take on | C．take in | D．take up |
16．It is usually not quite cold in this area in March，but sometimes temperature_______low．
| A．should | B．must | C．can | D．Shall |
15．Jack was once a common name，___________,I think, that is seldom chosen nowadays．
| A．it | B．one | C．who | D．Which |