disposable income 可支配收入
Since they don't have any children and their rent is very cheap, they've a lot of disposable income.由于他们没有孩子而且房租也非常便宜，所以他们手头可支配的收入相当宽裕。
>> conspicuous consumption
=buying expensive things to show people how rich someone is
Many people believe that conspicuous consumption is an antisocial behaviour.
>> levy a tax on...
= officially request payment of a tax
A new tax has been levied an cigarettes.
A small family car is more economical than a large car.
>> be cost-effective
=be economical in terms of the services received for the money spent
We need a cost-effective solution to the problem.
>> be penny-wise and pound-foolish
= be extremely careful about small amounts of money but not careful enough about larger amounts
These education budget cuts are really penny-wise and pound-foolish.
a source of income 收入来源
Edward does not have any other source of income apart from his job
>> scrimp and save to do sth.
=spend very little money because you want to save it to buy sth. expensive
They had to scrimp and save to pay for the holiday.