They can't see flowers in the picture.[ ]
A. some
B. a
C. an
D. any
答案：D
核电荷数为63的铕元素的相对原子质量值为152，则该元素的原子中，中子数=______，核外电子数=______．
—Isn't that Ann's husband over there?
—No, it ______ him. I'm sure he doesn't wear glasses. [ ]
A. is
B. isn't
C. are
D. wasn't
