三角片形端生牙
A．鱼纲 B．两栖纲 C．爬行纲 D．鸟纲 E．哺乳纲
参考答案：A
显微镜下看到的像的放大倍数是________和_________放大倍数的____________。
After hours of repair,the driver tried to start the car but it _______ work.
A．won.t
B．shouldn’t
C．wouldn.t
D．couldn’t
