Use semicolon or linefeed before 'done' (or quote to make it literal).

Problematic code:

for f in *; do echo "$f" done

or

echo $f is done

Correct code:

for f in *; do echo "$f"; done

or

echo "$f is done"

Rationale:

done only works as a keyword when it's the first token of the command. If added after a command, it will just be the literal word "done".

This is also true for other keywords like then.

Exceptions

If you're intentionally using done as a literal, you can quote it to make this clear to shellcheck (and also human readers), e.g. instead of echo Task is done, use echo "Task is done". This makes no difference to the shell, but it will silence this warning.