胆汁中促进脂肪消化和吸收的有效成分是（）。
A．脂肪酶
B．胆红素
C．胆绿素
D．胆盐
E．胆固醇
参考答案：D
—Who is the man over there? Is it Mr. Li?
—No, it _______ be him, Mr. Li has left for Hong Kong. [ ]
A. mustn't
B. may not
C. needn't
D. can't
完成句子
1. My grandparents worked (在田地里) ten years ago.
2. Life was ____ (不同的).
3. She cooked (在炉火上) last night.
4. Mr Black is (学汉语).
5. We live in (一所大房子).
