1.只要的英文怎么写

only when you learn how important it is can you put your heart into it. 只有当你了解它 的重要性， 你才会全身心投入去学习它。

只有在夏季才可以通行的山路. The mountain route that is practicable only in summer 只有受到挑衅时才以暴力还击 React with violence only under provocation,ie when provoked 只有人类才有理性. only man has reason。

2.1

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