下列动物中体内有脊柱的是[ ]
A．对虾
B．螃蟹
C．河蚌
D．泥鳅
答案：D
—Could I go out with my friends tonight?
—_____ But you can't stay out late..[ ]
A. No, you can't.
B. Yes, you can.
C. Sure, you can't.
D. Yes, you could.
船舶试验有哪几类？
