buy as required

例句：

1. 1. I need to buy some new clothes for the party.
   我需要为派对买些新衣服。
2. 2. He bought a new car last week.
   他上周买了一辆新车。
3. 3. She bought a house in the suburbs for her family.
   她为家人在郊区买了一所房子。