def adjust_top_mentions(mentions, subtoken_map, sent_start, sent_end):
    """
    Adjusts the top mentions indices to reflect position within an individual sentence.
    """
    adjusted_mentions = []
    for mention in mentions:
        if mention[0] >= sent_start and mention[1] <= sent_end:
            adjusted_start = subtoken_map[mention[0]] - subtoken_map[sent_start]
            adjusted_end = subtoken_map[mention[1]] - subtoken_map[sent_start]
            adjusted_mentions.append((adjusted_start, adjusted_end))
    return adjusted_mentions