-120____
下列各句中,加线 的词语运用错误的一项是( )
—When is ________ birthday?
—________ birthday is on April 20th.
-Don't throw away the waste paper.
-It needs __________ so that it can be reused.
若k>1,关于x的方程2x2﹣(4k+1)x+2k2﹣1=0的根的情况是( )