1. He ordered fried chicken last night.
2. He ordered a fried chicken last night.
3. He ordered two fried chickens last night.
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Which one is grammatical? When we order fried chicken a lot, what expressions can we use?
Only #1 is correct. The correct ways to phrase 2 and 3 are here:
He ordered a fried-chicken dinner last night.
He ordered two fried-chicken dinners last night.