Yes, "a plan" means one plan.
All are grammatically correct. The first sentence refers to more than one plan, but doesn't give a specific number. The second sentence refers to one plan. The third sentence refers to two plans.
=)
Let's make plans for next month.
Let's make a plan for next month.
Let's make two plans for next month.
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What is the difference among them?
Does a plan mean one plan?
3 answers
what part of speech is all
Kelsey -- please click Post a New Question and ask your question. It's very confusing when someone "piggy-backs" on another's question.