Hi, I know that is needed 30 months of physical residency within 5 years in USA in order to apply for citizenship. However, how does the immigration know if I was here for less that that? Do they relay on what we tell them or they can find it out somehow? The USA immigration scans passports only on re-entry to the country, so, how should they know how long I was out unless I tell them? Also, once a passport is renewed - before the citizenship application - there is no record on the new passport of old trips outside the USA. Any comment about this issue?