—Who is making so much noise in the garden?
—___________ the children.
| A．There are | B．They are | C．That is | D．It is |
--- Why is the cake so expensive?
---- Maybe you don’t know a cake made of wheat costs less than _____ made of rice.
| A．one | B．that | C．the one | D．another |
I _____ sooner but I didn’t know that they were waiting for me .
| A．had come | B．was coming | C．would come | D．would have come |
Experiments of this kind ___in both the U．S and Europe well before the Second World War．
| A．had conducted | B．have conducted |
| C．have been conducted | D． had been conducted |
The situation forced my mother and I exchanged our roles as child and caretaker, making me grow up much faster than the _____ child.
| A．average | B．ordinary | C．common | D．usual |
It is the first time that he ______ here and now it is high time that he ______ around.
| A．come; should be shown | B．has come; was shown |
| C．came; was shown | D．has come; be shown |