_______________ while writing, he locked himself in his study.
| A．Not to interrupt | B．Not being interrupted |
| C．Not to be interrupted | D．Being not interrupted |
The engineer buries himself in work all day long and has no time for some outdoor activities, __________ he has the interest.
| A．as if | B．even if |
| C．so long as | D．now that |
Can you write about a challenging situation ______ you once faced in your life and how you dealt with it?
| A．where | B．when | C．which | D．there |
I’m always ________ about what I say because careless remarks are likely to hurt others’ feelings.
| A．enthusiastic | B．curious |
| C．doubtful | D．cautious |
Evidence has been found through years of study __________ children’s early sleeping problems are likely to continue when they grow up.
| A．why | B．how | C．that | D．whether |
Two lawyers have donated $ 50, 000 to _________ our school’s campaign “Help the Needy”, which was started by our former headmaster 10 years ago.
| A．approve | B．advocate |
| C．guarantee | D．sponsor |