Passport - If you lose your passport, you must contact the Singapore
embassy to find out how to get
it replaced. It is also recommended that you contact the police and file a
report indicating when and where you think it was lost so that that information
is on file in case someone finds the passport and begins to use it for illegal
purposes.
Visa - Visas are only used for entering the U.S. so when you are already
inside the U.S., you don't need a visa. The only time you will need one is if
you leave the U.S. and want to re-enter. You will need to apply for a new U.S.
visa the next time you leave the U.S.
I-94 card - Replacing I-94 cards is expensive and often takes a long time
(may drag over a year). You will need to complete an
I-102 form ,
appropriate fee (US$100), and other supporting documents to USCIS in order to
get a replacement. You can try contacting an Advisor in OIE concerning this if
you want.
I-20 or DS-2019 (formerly IAP-66) - You can request a replacement of a
lost I-20 or DS-2019 at OIE.