So involved with computers ____ that the leaders at the summer computer camps often had to force them to break for sports．
| A．has the children become | B．did the children become |
| C．has become the children | D．became the children |
Besides the content of a book, _____the editor also cares about is the number of readers.
| A．who | B．why | C．how | D．what |
Life is a journey _____with hardships, joys and special moments.
| A．filled | B．to fill | C．filling | D．having filled |
——Lily is going to make a presentation in class this afternoon.
—Oh, really? I _____it was Michael’s turn.
| A．think | B．have thought | C．thought | D．am thinking |
_____H7N9 is a deadly virus, it is still safe to eat thoroughly-cooked chicken.
| A．Until | B．While | C．If | D．Since |
The house is dirty because itsince they moved out.
| A．doesn’t clean | B．isn’t cleaned | C．hasn’t cleaned | D．hasn’t been cleaned |