Let's talk about our vacation plans.

1. I'm planning to visit my grandparents.
2. I'm planning to visit my grandparents'.
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Which one is commonly used, #1 or #2?
When a person say #1 or #2, they are pronounced the same. So in this case, does it mean #1 or #2?

1 is what is needed to answer the question. (2 seems to meanyoull be visiting their house, whether they’re there or not!). I’d use only 1.

Both #1 and #2 can be used to convey the same meaning, but there is a slight difference in usage between them.

1. "I'm planning to visit my grandparents."

This sentence implies that you are planning to visit your grandparents as a whole unit, which includes both your grandfather and grandmother at the same location.

2. "I'm planning to visit my grandparents'."

This sentence suggests that you are planning to visit multiple locations belonging to your different grandparents. For example, you might be visiting your paternal grandparents' house on one occasion and your maternal grandparents' house on another occasion.

In terms of pronunciation, both #1 and #2 are pronounced the same way, as the apostrophe in #2 represents the possessive form of "grandparents" as well.

So, the choice between using #1 or #2 depends on whether you are referring to visiting your grandparents as a whole or visiting multiple locations belonging to different sets of grandparents.