He _____the problem _____in his mind for a whole week before he did anything about it.
| A．switched; on | B．kicked; up | C．turned; over | D．took; on |
The naughty boy to me that the hen that there just now had two eggs the day before.
| A．laid; laid; laid | B．lied; lay; laid | C．laid; lay; lain | D．lied; laid; lain |
is even more important is the earth cooled down, water began to appear on its surface.
| A．When; that; when | B．What; whether; as | C．What; that; as | D．lt; whether;  as |
Going on a trip into space must be quite exciting experience.
| A．/;the | B．the; the | C．the; an | D．/; an |
Though having lived abroad for years, many Chinese stillthe traditional customs.
| A．perform | B．pssess | C．observe | D．support |
He is still his story that his car was stolen and later returned, but the police don’t believe him at all.
| A．agreeing on | B．dealing with | C．thinking about | D．sticking to |