For example, although I didn't decide to which shop to go, why can't the sentence "I will go to a shop" be accepted.
And what's the difference between these sentences : 1) I left my purse in a car 2) I left my purse in the car
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Sign up to join this communityFor example, although I didn't decide to which shop to go, why can't the sentence "I will go to a shop" be accepted.
And what's the difference between these sentences : 1) I left my purse in a car 2) I left my purse in the car
I do not know why you believe the first of your examples is unacceptable. It will sound idiomatic to users of at least American Englsh.
"I went to a shop to get some winter clothing" and "I went to the shop to get some winter clothing" are both acceptable English sentences, but they have slightly different meanings. The first sentence does not specify which shop was used because the specific shop is not relevant. The second specifies a particular shop, presumably one defined by a previous sentence or by context.
There is therefore nothing wrong grammatically with your second set of examples. However, the first sentence in that pair is very unlikely to occur because it implies that you definitely know that you left your purse in some car or other, but do not know which car. That set of circumstances could arise, but would certainly be infrequent.
Nor would you use an indefinite article with a place name such as London. "I went to a London" implies that, of the many places named London, the actual one to which you went is irrelevant.