1. Today these observations can seem quite commonplace, yet looking back one must view them as a solid landmark in malaria research.
    现在这些观察看上去好象很平常，然而回首往事时，人们定会把它们视为疟疾研究上一个坚固的里程碑。

2. All these computer uses have become commonplace.
    计算机的所有这些功能现在都变得很平常。

3. But custom, we have a way of thinking, is behaviour at its most commonplace.
    至于风俗呢，我们习惯地认为它是最普通的行为，

4. But custom, we have a way of thinking, is behaviour at its most commonplace.
    至于风俗呢，只是些司空见惯的行为而已。