-She needs to use the B-2 visa to reenter US, just like she came to US from China. Bring the B2 extension receipt to prove her legal stay in US. She will be offered a new I-94 if she is allowed to reenter US (still possibly she may not be allowed to enter US), but you don't know how long this new I-94 duration will be. Another problem is that her B2 extension may be denied. Thus, her 10-year B2 visa stamp also will be invalid. I don't suggest her to travel out of US during the B-2 extension pending.
真是这样的话,能否6月8日从大瀑布出境6月10日在从大瀑布入境?万分感谢!