有的人总说工作忙，没有时间学习，我认为问题不在忙，而在于你愿不愿意学习，会不会挤时间。要学习的时间是有的，问题是我们善不善于挤，愿不愿意钻。Translation, albeit with a loss of elegance.
一块好好的木板，上面一个眼也没有，但钉子为什么能钻进去呢？这就是靠压力硬挤进去的。由此看来，钉子有两个长处：一个是挤劲，一个是钻劲。我们在学习上，也要提倡这种‘钉子’精神，善于挤和善于钻.
Some people always say work is too busy, there's no time to study; I don't think it's about being busy, but about whether you want to study or not, and whether you know how to squeeze (make) time. If you want to learn things, there is time, problem is whether we're willing to make time.*Or at least, it was purported to be written by him in his diary, which is full of "flowery language" praising of chairman mao and communism. However there are critics who believes that this is a fabrication. Doesn't matter in this context, though, I hope.
A piece of wood has no holes on it, but why can a nail still squeeze inside? This is done by using pressure to force it in. Thus, the nail has two strengths: it can squeeze, and it can drill/pierce. When we learn, we should also use this "nail" mentality: willing to squeeze and drill/pierce (drive?).
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