---You’ve read the Frog by Moyan,haven’t you? ---Yes,I_______second time and I got a better understanding.
At the end of last class, the English teacher requested that the homework this morning.
A number of methods been used, but the number of animals still small in the forest.
If ,the experiment will be successful.
such heavy pollution already, It may now be too late to clean up the river.
The spokesman didn’t make clear why the president failed to attend the conference.