We could have invited more people. There are spare seats at the back!

我们本来能够邀请更多的人的，后面还有空座呢！

I’ll go and see if there are any spare seats.

【spare】我去看看是否还有空余的座位。

There was not a single spare seat on the plane, nor on many of the 108 others that departed for the same destination that day.

飞机上没有一个空位，当天飞往同一目的地的108个其他航班中也都满员了。

Pigwidgeon was once again hidden under Rons dress robes to stop him from hooting continually; Hedwig was dozing, her head under her wing, and Crookshanks was curled up in a spare seat like a large, furry ginger cushion.

小猪又被罗恩的礼服长袍遮住了，因为它不停地尖声大叫；海德薇脑袋缩在翅膀下打瞌睡，克鲁克山蜷缩在一个空座位上，活像一个大大的、毛绒绒的姜黄色靠垫。