A traveler was a welcome break in an otherwise dull existenc
A traveler was a welcome break in an otherwise dull existence.此处:a welcome break
看到不少解答说a welcome break 是宾语,但是它是跟在系动词was后面的,而且是来描述traveler的特征的,为什么不是表语,如果是表语,那么in an otherwise dull existence可以理解为状语吗?