μέλλει [10 verses] (verb 3rd sg pres ind act) "Shall" is from mello, which means to "be destined or likely to," "might have, " "must surely have," "to be about to," "to be always going to do," "delay," and "to put off." -- - (WW) "Shall" is a Greek verb, which means "to be destined or likely to," "to be about to do something," or "to intend to" or "to have in mind to." This is not the future tense of the following verb, but the active verb in the clause. The following verb is an infinitive. Jesus only uses this verb in ten verses;

μελῶν [2 verses](noun pl neut gen) "Members" is melos, which means "limb", "feature", "form", "a musical phrase," and "the music to which a song is set." -- The word translated as "member" primarily means "limb." However, it also means a "feature," that is, a part of the whole. However, coupled with the one, it suggests a double entendre for another part of the body that is more like a limb.

μὲν [31 verses](partic) "Indeed" is men , which is generally used to express certainty and means "indeed," "certainly," "surely," and "truly." Alone in a question, it assumes the answer like "I take it" or "isn't it."  Used with the conjunction de,  it points out the specific word being contrasted after the conjunction. In English, we usually say, "on one hand...on the other hand." See the article here for specific uses with other particles.  -- The "truly" here is a particle, which, when used alone, expresses certainty, "truly" and "certainly." Alone in a question, it assumes the answer like "I take it" or "isn't it."  However, when used with the conjunction translated here as "but" takes on the meaning "on one hand..." with the "on the other hand" identified by the "but" phrase.

ἔμεινεν [27 verses](3rd sg aor ind act) "Abide" is meno, which, as a verb, it means "stand fast" (in battle), "stay at home," "stay," "tarry," "remain as one was," "abide," and (transitive) "await." -- The word translated as "remain" has the sense of to "stay," "stand fast," or "remain." This word is usually translated as "abide" in the KJV and "continue" in other Biblical translations. Though translated as "abide," it does not mean to stay in a dwelling place.

Μήποτε [2 verses](adv) "Not so, lest" is mepote, which means "never," and "on no account." As a conjunction, "lest ever." Literally, it means "not when." It takes a subjunctive verb like an "if/when" statement. -  The word translated as "not so, lest" is from an adverb, which means "never" and "on no account." Used in prohibitions with an aortic subjunctive. Today, we would say "no way!" Literally, the Greek word means "not when."