Nick had an unusually clever mind, so his success had been () and never in doubt.

单项选择题I was just coming out of the sea after a swim () I stepped on a sharp stone and cut my foot.

A．then
B．as
C．when
D．while

单项选择题--Why are you () all the pictures --I'm going to paint the walls.

A．hanging up
B．taking down
C．carrying out
D．putting off