"Be seated" is a phrase that indicates one should sit down comfortably. There are various synonyms for this expression, including "sit down," "take a seat," "plant oneself," "park oneself," "rest one's rear," "plonk oneself," "settle down," "assume a seated position," "be perched," "be stationed," "be propped," and "be installed." All of these terms convey the same meaning as "be seated" and can be used interchangeably in different contexts depending on the tone and formality of the situation. It is always best to choose the right synonym that fits the tone and context of the sentence.