We were just about ready to leave _____ it started to snow.
| A．when | B．before |
| C．after | D．since |
This is the reason _______ he was absent.
| A．that | B．which | C．why | D．what |
Listening to loud music at rock concerts ____ caused hearing loss in some teenagers.
| A．is | B．are | C．has | D．have |
______ the task is difficult, they managed to complete it on time.
| A．Because | B．Therefore | C．As | D．Though |
That’s where I _______ live when I was a child.
| A．used to | B．was used to | C．was using to | D．am used to |
Though lacking________, the young teacher manages the class very well.
| A．experience | B．experiences |
| C．experienced | D．experiencing |