从理论上讲,色相的数目是()。
A.无限的
B.有限的
C.七种色
D.72种色素的组合
参考答案:A
—Excuse me. How can I get to the library?
—walk along this street_______ you see the traffic lights. You will find it on your left.
A.before
B.after
C.until
D.when
带蒂皮瓣第二次断蒂术,一般应在第一次手术后()
A.7~14天
B.14~18天
C.18~21天
D.21~30天
E.30~40天