If the filter has been saturated with motor oil, it should be discarded and replaced.

如果过滤器已被机油浸透，就应该丢掉并更换一个。

《柯林斯英汉双解大词典》

Outdated theory should be discarded.

过时的理论应当抛弃。

youdao

To simplify means to choose those elements of the system that are worth including and those that should be discarded.

简化意味着要选择系统中需要包括的那些成分，和应该抛开的那些成分。

youdao

But it says the broad anti-defamation measures being sought by the Islamic Conference would have the effect of curbing debate about religious issues and should be discarded in favor of outreach and government defense of religious freedom and free speech.

VOA: standard.2009.10.26

It essentially is also a lie, and should be discarded, even by Bible believers.

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However, not everyone agrees that cultural traits should be discarded.

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He was a noted expert on the development of diagnostic questionnaires and other assessment measures, and his work was influential in determining whether an assessment method was valuable or should be discarded.

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