usually is not a prefix
Twentieth does not have a prefix. Just simple numbers do not usually have a prefix.
ex- is the prefix of experienced. Usually the first syllable in a word is the prefix.
Di- is the prefix in digestible. Usually the word's first syllable will be a prefix.
Wound does not have a prefix. Usually words with only one syllable don't have a prefix.
The word can does not have a prefix. Usually words that only have one syllable, don't have a prefix.
There is no prefix for it. Usually this is tuplet like octuplet.
The prefix for 'monition' is usually 'ad' . . . admonition.
It means "not" as in "not likely."
The prefix "hydro-" means water. It comes from the Greek word "hudor," which also means water.
A prefix for "to lose something" is "dis-". For example, "disappear" means to lose sight of something.
Usually it is aero, but it can be something else
No. Prefixes are easily spotted because 1) they are found at the front of words, 2) the part after the prefix is a word in itself, and 3) the prefix is not usually a word in itself. "Overjoyed" is not a prefix. It is an adjective.