如图所示的转化关系中,A、C为常见的气体,B常温下是一种液体,D为黑色固体.
判断,正确的填“正确”,错误的填“错误”.
连续的两个自然数相乘一定是偶数.
Do you see the sea? The sea is blue,and it is very large(大的).The sea looks beautiful in a sunny day. If(如果)you swim,in the sea,you know that the water is salty(咸的).Do you like the sea?
条件P:“x<1”,条件q:“(x+2)(x﹣1)<0”,则P是q的( )