______ is the key conception in Christianity in which the three aspects of the same God are united as one.

单项选择题A traditional food enjoyed by Americans during Thanksgiving Day is ______.

单项选择题The first president in U. S. history who resigned because of a scandal is ______.

单项选择题______ is the penname of William Sidney Porter, a famous short-story writer.

单项选择题Daddy and Father are ______ synonyms.