One way to build your vocabulary is to use word association. Every new word you come across find its synonym, antonym, collocation, fixed expression, idiom, and functional use. For example,
synonym: large, great
antonym: little, small
collocation: big and tall, big-screen version
fixed expression: that's very big of you
idiom: Big hitter - UsingEnglish.com
functional language: Would you have it in a bigger size?
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