A:a2<b2
B:ab<b2
C:
D:|a|+|b|>|a+b|
用所给单词的适当形式填空: I like riding____(bike).
Who has seen the film?
2,6,10,____,____,____.
蚯蚓刚毛的作用是( )
下列各式中,代数式的个数为( )
①b;②13;③x>5;④1x+2.