—What can you see?
—I can see a ____.
—Where is it?
—It's ____ the table.
—Oh, yes. “water and air is” should be “water and air are”.
已知集合A={1,2,3,4},B={2,4,6,8},则A∩B中元素的个数为( )
连线题:将下面成语与对应的历史人物匹配退避三舍____ a楚庄王问鼎中原____ b项羽卧薪尝胆____ c越王勾践破釜沉舟____ d晋文公