1. This job entails a lot of hard work.
    这项工作需要十分努力.

2. The teacher exhorted him to work hard.
    教师谆谆告诫他要用功.

3. The seed has a hard exterior covering.
    这个种子的外壳很硬。

4. The fundamental cause of his success is his hard work.
    他成功的根本原因是工作努力。

5. Their impregnable arguments are hard to rebut.
    他们牢不可破的论点很难被驳倒。

6. The sneakers he is wearing is quite incongruous with his formal attire.
    他穿的运动鞋与他的礼服极不协调。

7. The thief was wearing a mask.
    贼是带着面具的。

8. They tried hard to prevent the war.
    他们力图防止战争。

9. This kind of original painting is hard to procure.
    这种油画的原作是不易弄到的。

10. Their impregnable arguments are hard to rebut.
    他们牢不可破的论点很难被驳倒。