—As we know, planting trees is good for the environment. _______ will we plant trees on the hill?
—Maybe in two weeks.
A:How long
B:How soon
C:How often
D:How far
当市场商品价格波动时,会造成对生活必需品和高档耐用品的消费影响。下图中正确的是( )
人类社会的发展是一个从低级阶段向高级阶段进步的过程,在史前社会,母系氏族社会向父系氏族社会过渡的根本原因是( )