风湿热的发病年龄多见于()
A.5~15岁
B.3~18岁
C.4~16岁
D.1~15岁
E.2~14岁
参考答案:A
English people can't give up hamburgers or fried chicken because they're delicious. However, the French
are changing. They aren't interested in _______ food like before. [ ]
A. fast
B. healthy
C. natural
绘图题:请划出硅和锗两种二极管的伏安特性曲线。