数学不是一项观赏性运动；要理解它，必须积极参与其中。
Mathematics is not a spectator sport; to understand it, one must engage with it actively.
Small farms aren't relics—they're laboratories for innovation.
Never say never, because limits are just illusions.
过去总是紧张的，未来是完美的。
心的记忆会消除坏的，放大好的。