名 host，master，owner，possessor；动 lead，manage，advocate，stand for；形 main，principal，primary，subjective ；

[例句] 在主日学校她是她们班的班花。 She was the belle of her Sunday School class.

[例句] 在主室里，炽热的散热器暴露在外。 In the main rooms red-hot radiators were left exposed.