import re


def _looks_like_url(txt):
    """
    Return True if text looks like an URL (probably relative).
    >>> _looks_like_url("foo.bar")
    False
    >>> _looks_like_url("http://example.com")
    True
    >>> _looks_like_url("/page2")
    True
    >>> _looks_like_url("index.html")
    True
    >>> _looks_like_url("foo?page=1")
    True
    >>> _looks_like_url("x='what?'")
    False
    >>> _looks_like_url("visit this page?")
    False
    >>> _looks_like_url("?")
    False
    """
    if " " in txt or "\n" in txt:
        return False
    if "/" in txt:
        return True
    if re.search(r'\?\w+=.+', txt):
        return True
    if re.match(r"\w+\.html", txt):
        return True
    return False