用达尔文的自然选择学说不能解释的是
A:滥用抗生素造成细菌抗药性增强的原因
B:恐龙灭绝的原因
C:曼彻斯特地区深色桦尺蠖增多的原因
D:孔雀开屏的原因
If people ________ cutting down the forest, they will have nowhere _______.
写单词,补全句子。(每空一词)
A: ____ are you going to the party tomorrow?
B: I ____ going to go by car.
A. white B. orange C. pencil D. pen E. green
Hi, I'm Lucy. I have a pencil box. It's ____ I have a ____ It's black. I have an eraser. It's ____ I have a ____ It's red. I have a crayon. It's____