回複：EAD & H1b?

1) several months after filing I485, my 6-year H1b run out, then I switched to EAD. After reading some of this forum, seems to me it's better to stay on H1b in case I485 gets denied. Can I file 3-year H1b extension now? I don't think so, but like to know what you guys think.

Sure you can, but you need to go out of US to change back to H-1B after your H-1B approval.

2) my wife is on her H1b. If she switches to EAD, can she continue her H1b in case my I485 gets denied (without applying a new H1b for same empployer)
If she switches to EAD, she will be in the same boat as you, as after using EAD, her H-1b will be void.