My question is, should it be always followed by the preposition on? Oxford dictionaries gives the following. 只谈医学领域，其他行业不清楚。 一作10分以上的research artical，那是相当硬气的。 10分的文章绝对能成为您的一篇代表作。 肿瘤研究领域可谓神仙打架，最高if为292。 即便如此，if.
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Impact 通常指“ 重大的影响 ”，名词，动词形式都有。 我们先来看 impact: This change has no impact on the system's. Is the preposition in grammatical here?
Nowadays, we often see the word impact being used as a verb.
This change has no impact in the system's current behaviour. Her speech made a profound impact on everyone. I think we should have used on instead:
