adverbs: where about?

Sometimes I’m not sure where do I have to put adverbs in the sentence.
For example: “Doctor Smith took constantly part to research development.”
do I have to put it between subject and verb? or in this case is it better to place it between “took” and “part”?

Thank you for your help

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Doctor Smith took part continuously in research development.
Doctor Smith continuously took part in research development.
Doctor Smith took part in research development continuously
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Adverb placement is generally near the verb, but different types of adverbs exhibit different degrees of freedom. Other factors also come into play, as here: ‘take part’ is a phrasal verb that is inseparable except by adjectives (e.g. ‘took continuous part’).
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