If a group of similar things or people are strung out, they are in a long line with spaces between each one.

Most of Canada's population is strung out along its 5,525-mile border with the US 加拿大的大部分人口分布在与美国交界的5525英里长的边境上。

The geese were strung out along the river bank. 那些鹅沿河岸排成一列。

to make an activity last longer than necessary

I think the lawyer's just stringing out the case so that he'll earn more money. 我认为那个律师只不过是为多赚钱故意拖长案件受理时间。