In the 1950s in the USA, most families had just one phone at home, and wireless phones _______ yet.
A:haven't invented
B:haven't been invented
C:hadn't invented
D:hadn't been invented
句子变脸(按要求改写句子)。
①我只好垂头丧气地与她告辞了。(双重否定)
②我为什么不可以搞一个不是成衣的时装展呢?改成陈述句:
Touch and guess. ____
下图是2011年统计结果,我国耕地总面积为12173万公顷。读下面两幅图,结合所学知识判断下列关于我国土地资源的叙述,不正确的是( )