“Should I file tax return as Married filing jointly? That's what I did last and this year.”=====Of course however, it depends; UNLESS your spouse in China has taxable earned and unearned income , you can file your US return as MFS; as long as you file your US returns(fed and sate returns) jointly, you need to report all of your taxable US source and world wide income(including earned income that you/your spouse earned in US and China);however, if you file your US returns under MFS status(since your Chinese spouse doesn't have any U.S. income, she is not required to pay taxes on her Chinese income to the IRS. In such case, you can choose the marriage filing separately for your own tax return), then, you need to report only your taxable earned income/unearned income that you earn in US (as you have no income that you earned in China)to the IRS/state.SO, you need to weigh your options whether you choose to file joint return (MFJ), you want to file separate returns (MFS) .If you and your spouse decide to file jointly, you have to declareyour worldwide income (including exemptions, deductions and credits) as a couple in your U.S. return. Joint filing assumes you elect to be taxed on all your worldwide income and supply all pertinent and necessary documentation of tax liability. Filing separately has higher tax rates and fewer benefits (you won't be able to claim the elderly and disabled tax credit, child and dependent care tax credit and earned income tax credit, among other deductions and credits). Yet, filing separately generally releases you from the burden of any issues or lies made by your spouse in their own tax return.
“How many months should I answer to the question that whether my daughter is living with you? I answered '1 month' last year while interpreting that YOU as me only; then realized that YOU could mean me and my wife cuz I filed married filing jointly, I answered '12 months' this year.Did I answer any of these wrong?”===To claim your daughter in China as your dependent as your qualifying child,you must have lived with her for more than half the year, the person must have been in your home.