By + Gerúndio: Qual significado de "by"?

Dan. M. 1
I notice that is often the use of preposition "by" with some verbs in Present participle ( "Gerúndio" in Portuguese)such as in the following sentences:
* ...by reading the following questions.
* By continuing to listen to this message...
* How to learn English by using Google?
* By helping others we help ourselves...
* Is architecture best taught by practising architects?
So, I can't understand the meaning and the reason to use this preposition before -ing verbs. Somebody explains the meaning? When we must use "by" before -ing verbs?

Beforehand, thanks for your replies.

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2 respostas
Donay Mendonça 22 107 1.6k
Dan.M,

Assunto já discutido no fórum. Veja o link:

"By" indicando como algo é feito
Dan. M. 1
Ok, thank you Donay!