凡是可以作为()的岩层,无论成层厚薄,均就单独划分,不能并入相邻其他岩层。
参考答案:标志层
正确排列括号中的字母,组词填空。
1. Susan became an _____ (dingnatoust) writer when she was thirty-two years old.
2. Leona broke the world _____ (rdrcoe) three times during 1987-1989.
3. Where _____ (erwe) you born, Cathy?
4. Jackie Chan is a great action _____ (veimo) star.
5. When you _____ (eeznse), you'd better use a handkerchief (手帕).
关于十二指肠球部溃疡,下列说法不正确的是()
A、常见球部变形
B、溃疡可多发
C、可开成慢性增强
D、可至胃蠕动增强
E、部分可恶变