Sorry but this question might be very basic. Could you please tell me what is the grammar behind the Latin phrase "mutatis mutandis"? I checked Wiktionary, and discovered that this phrase was composed by two participles, or one verb and one participle. If we are to think this alone the one-verb line, then shouldn't the meaning of this be "you are to be moved or changed" ? As for the two participles, I don't think I know anything about it from class, yet.
Can't not thank you enough
The form of the phrase is that of an Ablative Absolute. Check the index of your Latin book if you haven't gotten to it yet, or see Allen & Greenough's New Latin Grammar, Section 419
(www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0001%3Asmythp%3D419). Such a phrase is called "absolute" because stands independent of the grammar of the main sentence. An example of such a phrase in English would be: God willing, I will survive this disaster. "God willing" here is an absolute phrase, standing independent of the main sentence.
In English, these phrases stand in the nominative case because English does not have an ablative case. In Latin, such phrases stand in the ablative case (ablative of means or circumstance).
In form, "mutandis" is a future passive participle (gerundive) in the neuter plural acting as a substantive (noun), literally, "the things to be done." "Mutatis" is a perfect passive participle in the neuter plural agreeing with "mutandis", literally, "having been changed." Thus, the phrase literally could be rendered: The things to be changed having been changed.
The phrase is used to refer to changing references in a statement to apply it to a different situation. For example: The procedures for training dogs can be applied, mutatis mutandis, to training cats. In other words, whatever procedures are used to train dogs can be used to train cats, if those procedures are changed in accordance with the different requirements of cats. It thus serves as a kind of shorthand, without having to detail each of the changes to be made for the new situation.
Such a phrase provides a good example of how pithy Latin is as compared to cumbersome English in being able to express in just two words what English takes at least eight to express.