（）年8月苏联成功的爆炸了第一颗原子弹，打破了美国对原子弹的垄断地位。
A.1949
B.1948
C.1950
D.1947
参考答案：A
— Mom, I was the first to reach the top of the mountain.
— Good job, Charlie. I’m ______ of you.
A．tired
B．proud
C．sure
D．sick
