Question

1. We can invite all our friends if we have a bigger house.

2. We will invite all our friends if we have a bigger house.


3. We could invite all our friends if we had a bigger house.

4. We would invite all our friends if we had a bigger house.

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Are the four sentences grammatical? Would you let me know the diferences? Thank you.

Answer 1

#2 is factual. The others are possibilities. All are grammatically correct.