它有三个定语修饰它。

It is qualified by three attributes.

youdao

这是因为一旦知道药效基因，药物化学家就可以修饰它，在保持药效的基础上减少毒性。

This is because once a pharmacophore is known, medicinal chemists can modify it to reduce toxicity while maintaining (or enhancing) potency.

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当甲基加到组蛋白后，这些基团会修饰它的性质并改变它上面特定基因的表达频率。

When methyl groups are added to a histone, they modify its properties and alter the frequency at which a particular gene is expressed.

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In the Beginning" can modify the verb "taught" as easily as it can the verb "rose." It can either verb assume, just as Milton's angels can "either Sex assume."

最初“还可修饰动词“宣讲“,也可修饰动词“生出“，它可修饰任意一个动词，正如弥尔顿笔下的天使可以“化男作女“

耶鲁公开课 - 弥尔顿课程节选