下列选项中,属于意志薄弱的表现有( )
①知难而进,迎难而上 ②明知山有虎,偏向虎山行
③知难而退,逃避困难 ④临阵退缩,虎头蛇尾,前功尽弃
A:①②
B:①④
C:②③
D:③④
There are five ____ (people) in his family.
曾有人问位哲人:“一滴水怎样才能不干涸?”哲人回答说:“把它放到大海去。”这简短的对话,揭示了一个深刻的道理是( )
已知函数f(x)对任意的a,b∈R,都有f(a+b)=f(a)+f(b)﹣1,且当x>0时,f(x)>1
(1)判断并证明f(x)的单调性;
(2)若f(4)=3,解不等式f(3m2﹣m﹣2)<2.
____you like to go with me?