def ctm_to_dict(ctm_fn):
    """
    Return a dictionary with a list of (start, dur, word) for each utterance.
    """
    ctm_dict = {}
    with open(ctm_fn, "r") as f:
        for line in f:
            utt, _, start, dur, word = line.strip().split(" ")
            if not utt in ctm_dict:
                ctm_dict[utt] = []
            start = float(start)
            dur = float(dur)
            if not "<" in word:
                ctm_dict[utt].append((start, dur, word.lower()))
    return ctm_dict