"分期付款"用英语可以说成"installment payments"。
这个词来源于拉丁语"installare"，意思是"安装"或"安置"，后来在英语中引申为"分期"的意思。
例句：
I can't afford to pay for the car all at once, can I make installment payments?
（我一次性付不起这辆车，能分期付款吗？）
The furniture store offers a financing plan with low monthly installment payments.
（家具商店提供低月供分期付款计划。）
He had to take out a loan to make the installment payments on his new house.
（他不得不借钱来做新房子的分期付款。）