Mary is really good at taking notes in class. She can almost every word her teacher says.
-Would you mind if I take the seat? - .
The bell rang and came in Mr.Brown, a book in his hand. Then the class began.
In the past 5 years a great deal of money _____ improving the environment of the school.
China has been working very hard to stop the endangered animals ______ .
I ______their method of making the machine .