如图所示有一正方体木块漂浮在水中，请画出木块受到浮力的示意图．
答：浮力的示意图如下：
以“一般贸易”监管方式申报进口废铝，应向海关提交（）。
A.入境货物通关单
B.废物进口许可证
C.自动进口许可证
D.进口许可证
As is known, mobile phone make it possible for people to____each other conveniently.
A．keep in touch with
B．get in touch
C．lose touch with
D．be connected
