def _cut(match):
    """
    Cut matched characters from the searched string.
    Join the remaining pieces with a space.
    """
    string, start, end = match.string, match.start(), match.end()
    if start == 0:
        return string[end:]
    if end == len(string):
        return string[:start]
    return ' '.join((string[:start], string[end:]))