在Java语言中，不是标识符组成成员的是( )。
A．字母
B．数字
C．下划线
D．@符号
参考答案：D
林场有松树270棵，杨树90棵，杨树的棵树比松树少百分之几？
用括号内所给词的正确形式填空。
1. Have you ever seen this kind of _________ (music) instrument?
2. England is a _________ (Europe) country.
3. The basketball match was very _________ (wonder).
4. I have _________ (discover) English is very useful.
5. The twins have been to the _________ (unite) States.
