"On" isn't the only preposition

There seems to be an overuse of the preposition "on" in casual and formal speech these days. I see it less in writing, but not I week goes by where I hear someone speak and think "that's not the preposition you want in that sentence."

You might remember that prepositions are "anything a mouse can do." In other words, words like on, in, over, under, around, into, about, behind, between. Here's a neat graphical representation:

http://publish.illinois.edu/wolof201fall14/files/2014/09/exo.jpg

Grammatically, it's a little bit trickier when prepositions are used to modify things that aren't physical, like a topic or an issue (e.g., "What are the known facts about that issue?"). Where I hear this most is the replacement of "about" or "for" with "on." I'm not sure if it's our urge to save a syllable, or just our obsession (an over-obsession sometimes) with making our language more active and "verbing" everything (i.e., "on" is more concrete than "about"). But here are the types of phrases I hear and better phrases IMHO.


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"I need to think on that?"

Better...

"I need to think about that?"

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"What are our plans on that project?" 

Better...

"What are our plans for that project?" 

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