对于分词短语在句中做后置定语和伴随状语的判断,还要whilst作为连词和名词的用法判断

句子为 they were at their happiest whilst playing soccer

以下是我对句子的分析:(1)当whilst为连词成分时用法于while相同，那么原句为they were at their happiest whilst （they were） playing soccer，（they were 可以省略），那句子意思为他们最开心的是当他们踢足球的时候。

（2）当whilst为名词成分，其意思为一会儿、一段时间，此时句意为他们踢足球的时候最开心了，根据此句意我判断playing soccer 为伴随状语，对此我很纠结它是做伴随状语还是后置定语。