In many cases, moving, one foot gets trapped inside (5)
I believe the answer is:
often
'in many cases' is the definition.
(I've seen this before)
'moving one foot gets trapped inside' is the wordplay.
'moving' indicates an anagram.
'foot' becomes 'f' (abbreviation).
'gets' becomes 't' (I can't explain this - if you can you should believe this answer much more).
'trapped inside' indicates putting letters inside.
'one'+'f'='onef'
'onef' with letters rearranged gives 'ofen'.
'ofen' placed around 't' is 'OFTEN'.
Can you help me to learn more?
(Other definitions for often that I've seen before include "Much of the time" , "More than occasionally" , "Regularly" , "Repeatedly with regularity" , "Frequently, at short intervals" .)