tack

n. 大头钉,行动方针
v. 以大头针钉住,附加,跟随

My mother tacked the sleeves on before sewing them.

我妈妈在把袖子缝好之前，先用大针脚把它缝好。

The speaker suddenly changed tack and left us all rather confused.

演讲人突然改变了论调，把我们都搞糊涂了。