Clearing a variable within for loops

I am running a loop but the variable used sometimes doesn’t get a new string written to it. How can make sure the variables are cleared at the end of every loop?

I realize the ${LOOP} internal variable does this automatically. Is there anyway to have multiple internal loop variables so that nested loops could be accomplished?

If the answer is no that would make the first question all the more pertinent.

Thank you!

hmm… every normal variable gets reset when a new LOOP starts, or?

The only vars that get not reset are global variables