More dinosaur fossils（化石）, including footprints, bones or eggs（ ）
| A． |
discover |
B． |
be discovered |
| C． |
have discovered |
D． |
be discovering |
I didn't do very well in this exam．Unluckily，he did it ．（ ）
| A． |
worse |
B． |
badly |
C． |
better |
D． |
worst |
The water dark and dirty．It's no longer safe to drink．（ ）
| A． |
became |
B． |
has become |
| C． |
will become |
D． |
was becoming |
Last night，the shop was closed she didn't buy any chocolate．（ ）
| A． |
so |
B． |
if |
C． |
or |
D． |
when |
Some old people need a _______ because they feel lonely．（ ）
| A． |
gift |
B． |
stick |
C． |
pet |
D． |
watch |
By the time the teacher came, we ______ cleaning the classroom．（ ）
| A． |
finished |
| B． |
have finished |
| C． |
had finished |