使用AWS Transcribe进行单词同步的解决方案是使用Amazon Transcribe对音频文件进行转录，然后通过调用Amazon Polly来将文本转换为语音。具体实现可以参考以下Python代码示例：

import boto3

transcribe = boto3.client('transcribe')
filename = '/path/to/audio/file'
job_name = 'job_name'
transcribe.start_transcription_job(
    TranscriptionJobName=job_name,
    Media={'MediaFileUri': 'file://' + filename},
    MediaFormat='mp3',
    LanguageCode='en-US',
)

while True:
    status = transcribe.get_transcription_job(TranscriptionJobName=job_name)
    if status['TranscriptionJob']['TranscriptionJobStatus'] in ['COMPLETED', 'FAILED']:
        break
    print("Not ready yet...")
    time.sleep(10)

if status['TranscriptionJob']['TranscriptionJobStatus'] == 'COMPLETED':
    transcription = status['TranscriptionJob']['Transcript']['TranscriptFileUri']
    response = urllib.request.urlopen(transcription)
    data = json.loads(response.read().decode())
    result = data['results']
    for res in result['items']:
        print(res['alternatives'][0]['content'])
    print('Conversion complete.')
else:
    print("Conversion failed.")

该方案可提供将转录的文本与音频同步的单词级别的精度。