要将女用衬衣归类于相应的子目时,首先确定四位数级品目号,然后确定其相应的一级子目号,最后再在该一级子目内确定其相应的二级子目号,对其他的一级子目则不必查看了。
参考答案:对
----Are you a volleyball player in your school?
----Yes. I_____the team a year ago and I ____on the team for a year.
A.have joined, have been
B.was joined ,am
C.joined,was
D.joined, have been
写出下列反应的离子方程式:
(1)Al2O3溶于NaOH溶液:_______________________
(2)Al与NaOH溶液反应:_______________________