If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.
There is no friend as loyal as a book.
美联储目前没有预测会出现经济衰退。
天下战乱不断,朝中何人敢主动请战?