大量事实表明投资者普遍喜好高风险高收益，希望期望收益率和风险越大越好。（）
参考答案：错
选择正确的单词填空。
l. There ____ (is/are)a boy.
2.There ____ (is/are) some apples.
3. Please (don't/doesn't) sing!
4. What ____ (is/are) you doing?
5. You're (to/too) loud.
6. I see many people ____ (flying/fly) kites in the park.
未成熟型畸胎瘤属于（）
A.肉瘤
B.早期胃癌
C.良性肿瘤
D.恶性肿瘤
E.癌前病变
