Question

句末in a few years那动词用什么形态？

Answer 1

in a few years，几年后。
动词用一般将来时态。

In a few years, their attention will turn to the annual ritual of shopping for a PROM dress, and by then their fashion tastes will have advanced still more.
几年后，他们会开始关注每年举行的正式舞会的着装，那个时候他们的衣着品味会有所提高。

Answer 2

答：在含有介词短语in a few years（ 在几年之内、在几年之后）的句子中，其谓语动词可以用一般将来时，也可以用一般过去时。