it's very imporant for us to learn englsh by--------(make) flashcards

it's very imporant for us to learn englsh by--------(make) flashcards
it's very imporant for us to learn englsh by--------(make) flashcards

it's very imporant for us to learn englsh by--------(make) flashcards
making
by是介词,介词后面如果用动词,要用其ing形式.

making

by是介词，介词后跟动名词

making, by+doing.
用flashcards学英语对我们很重要

by介词后要用动词的ing形式，所以是making

It's very important for us to learn English by making flashcards.制作抽认卡来学习英语对我们很重要。 by 后面要用动词的ing形式。