7.) I found my car that was stolen.

Thanks

#2 is grammatically wrong because "car" is singular. You cannot say "my car have". The only sentence that makes logical sense is #3. In #3, the structure is: SUBJECT = "I" VERB = "found" ADJECTIVE CLAUSE = "having been stolen" (modifies "car") The other sentences are poor but not 100% wrong. The main problem is that it is not the "car" that is "found". Let's take #7 as an example. The thing that is "found" is not the car but rather the fact that the car was stolen. To fix #7, you should say something like "I found that my car was stolen". All the other sentences have similar problems.

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