回复：也请教8老师几个填表的初级问题, 万分感谢!

1.  I-131 form's supporting letter, where should I get this letter,  International office or HR?

-Not need any support letter.

2.  My daughter is 10 years old, for her forms,  should she sign or I sign for her?

-Yes, you can sign her name for her using this format: "your child's name/by parent: your name".

3.  For the blanks that don't apply, should I leave them blank or I should write N/A?

-Leave it blank.

Thanks very much with all my heart!