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"I couldn't move for fear."

Can I use "with" in place of "for"?
How about "by" in this sentence?

If I replace prepositions, does it make any differences?

Many thanks in advance!!
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In this case, "for" is probably your only single-word alternative, although you may be able to replace it with a phrase. For example "I couldn't move because of fear."

Most languages (and English is no exception) use prepositions inconsistently - for example the notorious on/in confusion in English - but really, such inconsistencies are supposed to be the exceptions, not the norm. In general, prepositions have a MEANING. For your examples:

for = because of
with = in the same location as OR using
by = by means of OR beside

Rommie