原式=a2-b2a+b
=(a+b)(a-b)a+b
=a-b.
I think Leehom Wang is _____ pop music singer in China.[ ]
A. good
B. better
C. best
D. the best
Many teenagers have hobbies. But sometimes these hobbies can get ______ of schoolwork. [ ]
A. on the way
B. by the way
C. in the way
D. out of the way