Expression: "Don't write so big."

[Tom]

Hi

I am sure I have asked this question before, but can’t recall when and where. Could you please answer it again?

Can a teacher say these sentecnes to his students who are using a pencil? I mean, are these sentences correct and natural?

1- Don’t write so dark.
2- Don’t write so crooked.
3- Don’t write so big.
4- Don’t write so small.

Can dark, small, big be used an adverbs?

Thanks,

Tom

[Mister_Micawber]

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Yes, in speech at least.
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[Yankee]

Hi Tom

Both Webster’s and the American Heritage Dictionary list big and small as adverbs too.
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