English Prepositions

Unable to find a complete list of English prepositions on the net, I have set out to create one.
I believe I have a pretty complete list now.

I do not include phrases of more than one word (like "in front of"), nor do I include gerunds ("ing" forms of verbs, like "including").

about above across after against along
alongside amid amidst among amongst around
at as before behind below beneath
beside besides between betwixt beyond by
despite down during except for from
in inside into like near nearby
of off on onto out outside
over past since through throughout till
to toward towards under underneath until
up upon upside* with within without
* slang
Disputable Prepositions
but (meaning "except") doesn't seem to cut it on its own. It seems to need to be preceded by "all ..." or "everything ..." to have this meaning.
like (meaning "similar to") and as (meaning "in the capacity of") are included above as prepositions like the rest, but one must be careful with them, since they often look like prepositions when in fact they are not doing the quite the same thing as prepositions. Or are they?


Here is a simple "preposition test":
If you are wondering whether a word is a preposition, try putting it in the following sentence. If it makes sense, you probably have a preposition.

Prepositions are interesting to me because they seem to be the least well developed part of any language. (In other languages they may appear as postpositions, suffixes, prefixes, etc., and/or may be called some unenlightening term like "particle".) There are only a small number of them in any language, so each one (as well as various combinations) gets overloaded with numerous meanings, often influenced or determined by the specific verb used. They are some of the most basic, essential words of any language, yet it is practically impossible for non-native speakers to learn to consistently use them as a native speaker would.

Interestingly, almost all prepositions have a locational or temporal meaning.