Synonym for 'to follow up on something'

synonyms

Solution 1:

I would say :

regarding the earlier missive; with respect to, concerning. "your recent letter regarding the above proposal" Synonyms: concerning, as regards, with/in regard to, with respect to, with reference to, relating to, respecting, re, about, apropos, on the subject of, in connection with, vis-à-vis (Wikipedia).

pursuing the earlier missive; to carry on or continue (a course of action, a train of thought, an inquiry, studies, etc.).

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