烧嘴保护泵为（）泵，共有（）台。
参考答案：高压往复泵；2
怀疑胃癌者的首选诊断方法是（）。
A.X线钡餐
B.胃镜检查
C.B超
D.CT
E.核磁共振
These are our books , ? [ ]
A. aren't these
B. are these
C. aren't they.
D. are they
