回复：请教：我能换工作吗？

但是如果换工作，可以让新雇主马上根据老雇主的I140延长三年H1B吗（我的I140是今年五月拿到的）？
-Yes, if your old employer does not withdraw the I-140.

还是必须让旧雇主延三年后再迅速换工作？
-Yes, you can do that if you want.

还是现在根本不可能申请延期要到明年六七月份马上就要过期了才会给延期？
-You can only file the H-1 extension in advance 6 months before your current H1 status expires. If you do H1 transfer now, the duration of your H1 status can only 到明年七月. Then, you can extend it for another three years before your H1 six-year duration expires.