Hi Kerry-Kiang,
What effect your taxes is the amount of income and how much taxes was withheld throughout the year, if you are referring to W-2 income. If your income is not steady you just pay taxes on the amount of income you earn. If your standard deduction reduces your tax liability to zero, you may not have taxable income and everything you paid throughout the year for taxes will be returned to you.
Thanks,
Lydia
