债券与股票的区别表现在（）。
A.权利
B.目的
C.期限
D.收益
E.风险
参考答案：A, B, C, D, E
—Guess what. I've got a visa for Iceland this summer for a holiday.
—How nice! You ______ the very beautiful sights then.[ ]
A. have been enjoying
B. are enjoying
C. will be enjoying
D. will have enjoyed
属于胃癌溃烂引起的症状（）。
A.吞咽困难
B.上腹痛
C.恶心
D.体重下降
E.饱胀感
