He can hardly understand this matter because he is too young. 

A. Jane's refusal to attend his birthday party made him feel sad.

B. He felt sad not to be able to attend her birthday party.

C. Jane made him sad despite her refusal to attend his birthday party.

D. Jane refused to attend his birthday party because it made her sad.

A. Had my tutor not helped me, I couldn’t make such a good speech.

B. If my tutor didn’t help me, I couldn’t make such a good speech.

C. If it hadn’t been for my tutor’s help, I couldn’t have made such a good speech.

D. If my tutor hadn’t helped me, I could have made such a good speech.

A. We bought two bicycles, of which neither worked well.

B. We bought two bicycles which neither of worked well.

C. We bought two bicycles neither of which worked well.

D. We bought two bicycles, neither of which worked well.

A. The room for two months hasn’t been cleaned.

B. The room has been cleaned by nobody for two months.

C. The room hasn’t been cleaned for two months.

D. The room hasn’t been cleaned by somebody for two months.

A. They don't let workers use the office phone.

B. Workers are not permitted to use the office phone for personal purpose.

C. The office phone is supposed to be used by workers only.

D. They don't allow workers to make phone calls.

A. Competitive and demanding people believe that lifelong learning is the key to success in today’s labour market. 

B. Lifelong learning is believed to be the key to success in today’s competitive and demanding labour market.

C. Today’s labour market is competitive and demanding because people believe that lifelong learning is the key to success.

D. Believing that lifelong learning is the key to success, people now live in a competitive and demanding labour market.

A. He didn't forgive her for what she had done as he loved her.

B. He didn't forgive her for what she had done because she didn't love him.

C. She didn't love him as much as he loved her.

D. Although he loved her, he didn't forgive her for what she had done.