Our cake is on the table.
1. Yours is in the fridge.
2. Theirs is in the fridge.
3. Theirs are in the firdge.
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Among the three sentences, which ones are grammtical? Do we have to use 'is' or 'are'?
1 and 2 are fine. 3 is not.
1 and 2 are correct because the understood word is "cake" -- singular.