" If an employee fails to give you (고용주) a properly completed Form W-4, you (고용주) must withhold federal income taxes from his or her wages as if he or she were single with no other adjustments." https://www.irs.gov/taxtopics/tc753
택스 리턴 하실때 개인의 해당상황에 맞게 조정이 되니. . .CPA/EA 와 상담하시기 바랍니다.