1. I see a fly on my leg.

2. I saw a foreigner on the street.
3. I saw the foreigner on the street.
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In #1, 'on my leg' modifies 'a fly'? Am I right?
What about #2? Does 'on the street' modify 'a foreigner'? Or does 'on the street' modify the verb saw? What is the difference between these two sentences? What is the difference between #2 and #3? Does #3 mean that there was only one foreigner on the street?

1. In sentence #1, "on my leg" does not modify "a fly." It simply specifies the location of the fly. The prepositional phrase "on my leg" provides additional information about where the fly is situated but does not change the meaning of the fly itself.

2. In sentence #2, "on the street" can be interpreted in two different ways. It could modify "a foreigner," suggesting that the foreigner was present on the street. In this interpretation, the phrase provides information about the location of the foreigner. Alternatively, "on the street" could also modify the verb "saw." In this case, it describes where the action of seeing took place. The difference in meaning arises from whether the phrase modifies the direct object (the foreigner) or the verb (saw).

3. Sentence #3 explicitly states that the speaker saw a specific foreigner on the street. Unlike sentence #2, it implies there was only one foreigner being referred to. The definite article "the" suggests that the foreigner being talked about was previously mentioned or is known to both the speaker and the listener.

To summarize, the difference between #2 and #3 lies in the specificity and uniqueness of the foreigner being referred to. Sentence #2 leaves room for interpretation as to whether there were multiple foreigners on the street, while sentence #3 indicates a single known foreigner.