函数f(x)=12x-1的单调减区间是 ____.
You can visit Hong Kong in ______ season because there are many modern shopping malls there.
两直线3x+y﹣3=0与6x+my+1=0平行,则它们之间的距离为( )
关于分子和原子两种微粒的叙述正确的是( )