Just the discipline of having to put your thoughts in order with somebody else is very useful thing.
这是真的:要欺骗一个诚实的人是很难的。
气候变化对海洋生物构成最大威胁,我们必须立即采取行动减轻其影响。
竞争是好事,它迫使你不断进步。
Real friends are hard to find.