A:How long
B:How often
C:How far
D:How soon
106×72÷48=____
26460÷28÷63=____
在消化道内,下列哪组物质不经过消化可以直接被吸收( )
It was time ________ clean the house.
____
①德军突袭苏联 ②德军闪击波兰 ③日军偷袭珍珠港 ④柏林战役