Tom with his friends ( is ) playing soccer.为什么是is而不是are?

问题描述:

Tom with his friends ( is ) playing soccer.为什么是is而不是are?
Tom with his friends ( is ) playing soccer.为什么是is而不是are?

with是介词,与his friends构成介词短语,介词是不能做主语的,该剧主语是Tom.