Is this sentence grammatically correct?
"Remember that we don't put an -s at the end of uncountable nouns to make them plural, but there some that already have an -s at the end - so be careful!"
I think it should be "but there ARE some"
https://www.bbc.co.uk/learningenglish/english/course/intermediate/unit-3/session-1/activity-3

Question

Answer

Yes, you are correct.  It was probably a typo (a typographical error) or an editing error.

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