色多多在线观看播放-色多多在线观看高清免费-色多多在线观看视频-色多多在线看-欧美aaaaa性bbbbb小妇-欧美aaaav免费大片

A scientist in his laboratory is not a mere technician: he is also a child confronting natural phenomena that impress him as though they were fairy tales.

生活是一張白紙，每個人都在上面寫上自己的一兩句話。

I always prefer to believe the best of everybody; it saves so much trouble.

當我們有目的地疏伐森林時，我們不是在奪走生命，而是在為更多生命的繁榮騰出空間。

The true value of a forest is measured not just in board feet, but in biodiversity and ecosystem health.

Mathematics is not just about numbers, equations, computations, or algorithms: it is about understanding.