土的压实过程中起关键作用的是()。
A.土的级配
B.粘粒含量
C.土中水
D.空气含量
参考答案:C
下列关于克罗恩病的描述中正确的是()。
A.病变呈跳跃式分布
B.绝大多数患者有直肠受累
C.腹痛部位不固定
D.腹痛不明显
E.脓血便多见
History is ( ) a subject that only lets us know something in history; it also tells us a lot of truth.
A.less than
B.more than
C.no more than
D.not more than