[Originally posted on 05/10/12 on the Duolingo French for English speakers forum by blahedo]
Both “gros” and “grand” can be translated as “big” or “large”. When translating from English to French, a rule of thumb is that “grand” is used for things that get large by growing taller, and “gros” for things that get large by growing fatter or wider. For things that can get large in either direction, one word or the other can be chosen to nuance the meaning.
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