请教8老师，第三次申请回美证，说为了判断是给我再续一年还是两年，让我补材料，原话说的是
submit a photocopy of the pages in your passport to determine your time outside of the United States. Evidence shows that you departed the United States on July 29, 2017, but it is unclear when you returned from that trip. Arrival stamps after this date are needed to complete the adjudication of your travel document. This evidence will determine if your document will be valid for one year or two yeas.
问题1）我2017年7月之后进出美国几次，这次是要把所有的进出记录复印上交吗？
2）他们要这个材料来判断的principle是什么？是用我上一个两年内实际留在美国的时间长短？那是以前在美国呆的时间越短，越说明我需要出境，越容易给我续两年？还是反向的逻辑？
多谢！
