回复：H1b renew 需要离境连续的12个月吗？还是累计的12个月？

It can be  累计的12个月 with short break. See some information at these links:
http://www.avvo.com/legal-answers/regarding-1-year-gap-outside-us-after-6-years-on-h-154114.html
http://www.avvo.com/legal-answers/can-there-be-a-break-in-1-year-period--out-of-us---1166987.html
http://www.avvo.com/legal-answers/one-year-h1-b-l1-clock-reset-period-after-6-years--1653052.html