关于下列各装置图的叙述不正确的是 A.用图①装置精炼铜,a极为粗铜,b为精铜,电解质溶液为CuSO4溶液 B.图②装置的盐桥中KCl的Cl—移向甲烧杯 C.图③装置中钢闸门应与外接电源的负极相连获得保护 D.装置④中Ag电极发生反应:2H2O + 2e- = H2↑+ 2OH- 答案:D
The girls are playing badminton on the playground.What ________ the boys ________?
[ ]
A.
do, do
B.
is, doing
C.
does, do
D.
are, doing