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- Mules are very useful animals. 骡子是非常有用的动物。
- Horns are very useful weapons for some animals. 对某些动物来说,角是非常有用的武器。
- As we learn from what is said above, the tides can be very useful. 依照上面所说的，我们知道潮汐可以是非常有帮助的。
- Some epicontinental minerals are very useful. 有些大陆矿物很有用。
- Dictionaries are very useful to students. 字典对学生非常有用。
- These health checks are very useful to us. 这些体格检查对我们十分重要。
- These test pages are very useful. 这个测试页非常有用。
- S3: Bilingual classes are very useful to everybody. 学生3：双语课对（我们）每个人来说都非常有用。
- It's true that some ads can be very useful. 一些广告很有益是个事实。
- A .ashlight can be very useful in a storm. 手电筒在暴风雨时很有用。
- I found a gangway that proved to be very useful. 我发现一块很有用的跳板。
- Mules are a cross between a horse and an ass. 骡子是马和驴的杂种。
- The advice was very useful to me. 这劝告对我很有用。
- If space is not an issue,install them,as they are very useful. 如果空间不成问题，那么就安装它们，因为它们是很有用的。
- If you want my opinion,extracurricular activities are very useful. 如果你想听我的看法：课外活动是很有用的。
- These idioms are less popular but can be very useful. 这样的习惯用法并不太多见，但是可能会很有用。
- With this spirit everyone can be very useful to the people. 从这点出发，就可以变为大有利于人民的人。
- Good communication skills are very useful in business matters. 良好的沟通能力在商业事务中很有用。
- Variables are very useful if you want to store a value. 如果要存储值,变量则非常有用。
- Several mules are kept for farming. 几匹骡子保持在农田耕作。
