既要有原则性，也要有灵活性。

We should stick to the principles and be flexible as well.

他原则性很强，但从不爱挑剔。

Despite strong principles he was never censorious.

这种原则性的改变是如何发生的呢？

How did this shift in principles come to pass?

我国当代有关公务员制度中虽也有任官回避方面的原则性规定，仍不适应新形势下的新情况。

There are provisions in matters of principle on officials' challenge system in the contemporary public servant system, but they don't fit in with the new situation.