塑料一般是由()和()组成。
参考答案:树脂;添加剂
着色性干皮病的特征,除外()。
A.光敏感
B.色素改变
C.皮肤过早老化
D.癌变
E.汗斑
My sister likes watching sports on TV, _____ she doesn't play sports. [ ]
A. and
B. or
C. so
D. but