Tips For TaxpafsrsEvery single persona whose net income for the year 19*3 was $1,000 or more or whose gross income was $5,000 or more, and every mnrned couple (living together) whose net income was $2,000 or more or whose gross income was $5,000 or more, must file an income-tax return.Broadly speaking, gross income is all income received by the taxpayer during the year from salary or wages, business, trade, profession or vocation, dealing in property, interest, rent, or dividends, or from the transaction of any business carried on tor profit. Net income is gross income,|less certain specified de. ductions for business expenses, bad debts, taxes, etc.