tommjames: I simply defy anybody to search Google and scan the plethora of results that come back for this and say these people are speaking "weird" English.

Oy, oy, I'm not saying it's weird, I'm saying it's not tip-top, not 100% right - I'm speaking from an academic point of view here, not from a colloquial, normal, ĉiutaga sense.

However, with the group of English speakers I am surrounded by (South Australian speakers, particularly my family, uni mates, school mates, coworkers et cetera), "enter in" does sound rather weird - which is why I asserted that it might be a regional thing (just like how South Australians tend to say things like "Yeah I'm going heaps good" - maybe we South Australians don't use "enter-in" for some reason while everyone else does).

I'm just trying to liken it to things like "et cetera" - "and et cetera" does abuse the Latin a fair bit, but it's quite common to here "and et cetera". It's not entirely correct though, as it's the equivalent of saying "and and so forth".

EDIT: I just had a lecture on this topic actually - and it seems that "enter into" and "exit out of" are combinations of "enter" and "exit" and their prepositional equivalents, "go into" and "quit out of/get out of etc" respectively. After all, the more Latin it sounds, the more chic points your English gets, so what likely happened is that phrases like "go into" had the main verb replaced with a Latinate version (enter, in this case), but kept the preposition.

Anyway, I wouldn't personally recommend the forms "eniri en" and "eliri el" as the main way of saying "eniri" and "eliri" to people learning Esperanto (and subsequently "to enter into" and "to exit out of" to people learning English - I'd actually recommend the more Germanic equivalents). They can use it, it's OK, but it's not "within the system" so to speak and if the same patterns are deployed elsewhere in the language it might cause some confusion for the learner.

ceigered:Anyway, I wouldn't personally recommend the forms "eniri en" and "eliri el" as the main way of saying "eniri" and "eliri" to people learning Esperanto

I think you are missing the point. The point is that in some cases it is preferable and correct to use a simple "eniri" or "eliri", and in some cases, "eniri en" or "eliri el" is preferable and correct.

It depends a lot on the context. It definitely should not be implied that every single instance of "eniri" needs to be accompanied by "en", and likewise for "eliri".

Ah k, rightio... That clears things up then