His not coming our difficulties.
| A．added to | B．added up | C．added in | D．added up to |
Harry lived in London for three months,______ he learned some English.
| A．which | B．in which | C．that | D．during which time |
Those boys _____ many times not to go on line, but it doesn’t make any difference.
| A．have told | B．told | C．have been told | D．were being told |
Many old houses have been ____to make way for new roads.
| A．torn up | B．torn down |
| C．torn into | D．torn off |
____time,Chinese farmers have invented many farming techniques.
| A．Over | B．In | C．On | D．For |
When he ran downstairs, he tried to avoid ____by the teacher.
| A．being seen | B．seeing | C．to be seen | D．to see |