def sentence(*args):
    """
    SENTENCE thing1 thing2
    SE thing1 thing2
    (SENTENCE thing1 thing2 thing3 ...)
    (SE thing1 thing2 thing3 ...)

    outputs a list whose members are its inputs, if those inputs are
    not lists, or the members of its inputs, if those inputs are lists.
    """
    result = []
    for arg in args:
        if isinstance(arg, list):
            result.extend(arg)
        else:
            result.append(arg)
    return result