Need help with a sentence using gerund after Why did the author use "remembering" instead of "remember" in "principles that I think are key to remembering"

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occurred Dec 7, 2016 at 20:59

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edited Dec 7, 2016 at 15:52

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asked Dec 7, 2016 at 10:33

Need help with a sentence using gerund after to

I was watching a video about how to learn new vocabulary more easily, but I was stuck at this sentence spoken by the video author:

Now I'm starting with three basic principles that I think are key to remembering English Vocabulary.

I don't understand why the author used remembering instead of remember after to, is it a special grammar rule in this case or what?

grammar gerund-clauses