数学的快乐来自于为理解而奋斗。
Every tree we plant today is a promise to tomorrow.
这个世界是个美好的地方,值得为之奋斗。
The organism does not perceive stimuli, but objects in their environments.
对待心中的欲念,放纵即有所损,所以关键在于忍;改过向善,努力即有所助益,所以关键在于悔。