by RonPurewal Wed Apr 09, 2008 5:55 am
it's not ungrammatical, but there are slight differences in meaning between it and the present perfect progressive. (for the uninitiated, the p.p.p. is the 'has been going' construction.)
i'll make an analogy. let's discuss the following:
(1) he has lived in louisville since 1977
(2) he has gone to louisville since 1977
(3) he has been going to louisville since 1977
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i'll discuss (2) first, since it's most like the sentence you wrote.
i agree with you that (2) is pretty awkward.
it's essentially the opposite of he has not been to louisville since 1977; in other words, the sentence signifies that he has been to louisville at least once since 1977, but that's about all it really says. so, literally, your sentence just means that alex has been to the day care at least once since the age of one year.
(1) is technically ambiguous; it could mean either 'he has lived in louisville at some point since 1977' (in the same way as (2)), or it could mean 'he has been living in louisville since 1977'. if you want to resolve the ambiguity, then the present perfect progressive (has been living) is better; however, i think that, for static verbs (like has been, lived, is located, etc., as opposed to action verbs), the gmat tolerates this use.
(3) means that he has been going to louisville on some sort of regular basis since 1977 (whether yearly, monthly, or ... whatever). if you changed your sentence to the present perfect progressive, you'd effect the same sort of meaning.
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