Verily -- The word translated as "verily" is from the Hebrew word that means "truly" or "certainly," but it sounds like the Greek word with the same meaning. In Greek, the word also means "to reap." See this article discussing this "amen phrase."

I -- This is from the first-person, singular form of the following verb.

say -- The word translated as "say" is the most common word that means "to say," and "to speak," but it also means "to teach," which seems to be the way Christ uses it more frequently. It also has many ancillary meanings such as "to count" ("to number" or like we might say, "to recount" a story) or "to choose for yourself." Christ usually uses this word to refer to his own speaking or teaching.

unto -- This word "unto" comes from the dative case of the following word that requires the addition of a preposition in English, but the translator must decide which preposition to use: a "to" as an indirect object.

you,  -- The Greek pronoun "you" here is plural and in the form of an indirect object, "to you," "for you," etc.

All  - The word translated as "all" is from the Greek adjective meaning "all," "the whole," "every," and similar ideas. When it is used as a noun, we would say "everything." As an adverb, it means "in every way," "on every side," and "altogether." This word is in a form that can be either the subject or object of a sentence.

these  - The "these things" is from a pronoun that can mean "this" or "that," the nearer or the further depending on usage. As an adverb, it can mean "therefore" and "that is why." It is not typically used as an adjective. This word is in a form that can be either the subject or object of a sentence.

things -- Though the subject is plural, the verb is singular because neuter plural verbs are treated as a collective.

shall -- This helping verb "shall" indicates that the verb is the future tense or a form that indicates possibility at some time. Helping or auxiliary verbs are needed to translate the Greek verb forms into English.

come  - (CW) The word translated as "come" is a complicated one because it indicates a "coming" that has been completed, that is, "to arrive" or, even, "to be present." As a metaphor, it means "to be a follower." However, it is in the future tense and it doesn't match the "all these things" as a subject. The meanings of this word that take an object are that ideas of "depend up" and "relate to."

upon  - The word translated as "upon" means "against," "before," "by" or "on."

this  - The "this" is from a pronoun that can mean "this" or "that," the nearer or the further depending on usage. As an adverb, it can mean "therefore" and "that is why." It is not typically used as an adjective.

missing "the"  -- (MW) The untranslated word is the Greek definite article, which usually precedes a noun and, without a noun, takes the meaning of "the one." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those"). See this article for more. 

generation - The word translated as "generation" means "race" or "family." It is the word from which we get "genus" in English. Jesus uses it to refer to a type of person, specifically those like the Pharisees. His first describes this type earlier in Matthew as children who insist that everyone dance to their tune. His favorite adjectives describing of this type is "evil and adulterous," which in Greek, is closer to "worthless and cheating." In one previous discussion of this type, he compares them unfavorably with the people of Nineveh reacting to Jonah, and the queen of Sheba reacting to Solomon.