我国第一颗氢弹的爆炸成功标志着我国成为世界上第几个能够自己研制氢弹的国家[ ]
A．第三个
B．第四个
C．第五个
D．第六个
答案：B
—That must have been a terrifying experience.
—Yeah. I _____ in the damaged car, unable to move.
A．was stuck
B．have been stuck
C．am stuck
D．had been stuck
葡萄糖的作用是（）。
A．抑菌剂
B．等渗调节剂
C．抗氧剂
D．润湿剂
E．助悬剂
