衡量森林价值的真正标准不是木材的板英尺数，而是几个世纪的生态平衡。

Assume anyone asking for your account information for any reason is guilty of scamming you， unless proven innocent. The way to prove innocence is to call them back， or login to your account using numbers or a website that you provide， not them. Don’t release any identifying information while they are contacting you via phone， message or email. You must control the channel.

在数学中，你不是理解事物，你只是习惯了它们。

经济模型的价值在于其解释和预测的能力。