論壇大俠們好，
小弟有幾個問題，想請大俠們解答一下。公司想幫我辦PERM, 而我有幾個重要的問題想要請教大家（如果大家知道哪裏能找到答案的話，也可以給我個網址鏈接）：
1. 我能夠工作嗎？大概從什麽時候開始呢(如果從登廣告開始算起）？
-You need to have a status to work such as H-1B before you file I-485 and apply for EAD to work.
是不是I-140批準了就可以呢? I-140大概要多久才能批呢？EAD卡和I-140是一回事麽？如何能拿到EAD卡工作呢？
-You need to file I-485, then you can be qualifed for EAD application, then get the EAD to work. By the way, your priority date has to be earlier than the Date for fling immigration visa to be qualifed for filing I-485, which may take several years if you were born in Mainland China.
2. 用EAD卡工作會有風險嗎？拿EAD卡最長可以工作多久呢？會不會工作了半天，但是綠卡辦不下來？從I-140 被批到綠卡最長要等多久呢？
3. 在等待I-140被批期間能離開美國嗎？
-Yes.
在等待綠卡期間能離開美國嗎？
-Yes.
如果可以，最長能離開多久?
-Depends on what your status is. If you use AP, then maxium is less that one year.
最後，衷心感謝各位大俠的幫助，小弟不勝感激。
Leo
