I'm familar with this sentence.
When I play basket ball, I'm happy.
Then, How about 'where'? Can I use 'where' as I do 'when' like the following?
Where I play basket ball, there are a lot of people.
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Sign up to join this communityI'm familar with this sentence.
When I play basket ball, I'm happy.
Then, How about 'where'? Can I use 'where' as I do 'when' like the following?
Where I play basket ball, there are a lot of people.
Yes you are correct, they just have different meanings due to the changed pronoun.
For instance, "When I play basketball, I'm happy", means that you are happy whenever you are playing basketball (e.g. time).
However, "Where I play basketball, there are lots of people", means that there are lots of people at the place you play basketball.
But to answer your main question, you can use "where" in this sentence, but you could not use other common pronouns such as (what, how, who) without changing the structure of the sentence to a question form.
When and Where can be used in this context, but personally, I have found that when they are used like this, "whenever" and "wherever" are used instead, like this:
Wherever I go, people follow me.
Whenever I go to a shop, I look around for hours before buying something.
When you are using the extended forms of these pronouns, you can use others, such as "whatever" or "whoever":
Whatever I buy for my sister, she will like it.
Whoever wins will receive a prize of £1000.
In conclusion, yes, you can use both when and where in that sentence. "Where" should not be expanded (to wherever) in your case, because you are saying the precise location, so it is fine as it is.
As "when" can be expanded to make it more clear, these are the final sentences as I would say them:
Whenever I play basketball, I am happy.
Where I play basketball, there are lots of people.
Edit Just to clear up, "where" means one location, and "wherever" means any location