A:{x|x>1}
B:{x|x<0}
C:{x|x>1或x<0}
D:{x|0<x<1}
She was so busy ____(look) for her mobile phone that she didn't see a car coming.
下列属于鸟类特有的特征是( )
①体表有羽毛 ②用肺呼吸并用气囊辅助呼吸 ③体温恒定 ④通过产卵繁殖后代 ⑤前肢覆羽成翼 ⑥善于飞行.
如图为植物体某些生理过程的概念图,请写出标号所代表的文字.
①____ ,②____ ,③____,④____ ,⑤____ .