—Is she active? —No, she . [ ]
A. is
B. isn't
C. are
答案:B
朝は、早く()と思うのですが、なかなか起きられないのです。
A.起きよ
B.起きろ
C.起きよう
D.起きろう
设有关系模式SC(sno,cno,grade),查询既选修了c1又选修了c2课程的学生学号,正确的SQL命令是
A.SELECT sno FROM sc WHERE cno=“c1”AND cno=“c2”
B.SELECT sno FROM sc WHERE cno=“c1”AND SELECT sno FROM sc WHERE cno=“c2”
C.SELECT sno FROM sc WHERE cno=“c1”UNION SELECT sno FROM sc WHERE cno=“c2”
D.SELECT sno FROM sc WHERE cno=“c1”AND sno IN(SELECT sno FROM sc WHERE cno=“c2”)