A:must they
B:mustn’t they
C:haven’t they
D:have they
下列繁殖方式属于有性生殖的为( )
某军舰在西经20°,南纬59°的海面上,沿20°W经线向南发射导弹,射程为80千米,落弹点将在( )
The maths problem is very easy, so I can work it out ________.