missing "this"  -- (MW) The untranslated word is the Greek definite article, "the," 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.

My -- "My" is the regular first-person adjective in Greek indicating possession, so  "mine," "of me," "my," "relating to me," and "against me."

doctrine --  "Doctrine" is from a noun Jesus only uses here and in the next verse, means "teaching", "regulations" [military], and "discipline." Since Jesus is commenting on people wondering about his education, "learning" might work better here.

is -- The verb "is" here is the common form of "to be" in Greek. It means to have a certain characteristic or remain in a certain condition. It also equates terms or assigns characteristics. With the genitive object, the sense is "belongs to."-- When the verb "to be" appears early in the clause before the subject, the sense is more like "it is" or, in the plural, "there are."

not -- The Greek word translated as "not" is the Greek negative used to deny objective facts, not opinions. It means "no," "not," or"no truly." It makes a negative statement of fact. Adding "really" to the sentence captures the same idea. When a negative precedes the verb, it affects the whole clause. When it precedes other words, its force is limited to those words.

mine, -- "Mine" is the regular first-person adjective in Greek indicating possession, so  "mine," "of me," "my," "relating to me," and "against me."

but -- (CW) The Greek word translated as "but" denotes an exception or simple opposition. It is used to emphasize the contrast between things like we use "instead," "but instead,"or "rather." It is not the common word usually translated as "but." It is the Greek word "other" like we use "otherwise." Jesus often uses this conjunction to connect a negative clause, not doing something, with a positive one, "instead do this."

his  -- (CW) The word translated as "his" is the Greek definite article, without a noun, it has the sense of "the one." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those") than the English "the." See this article for more. 

that -- (IW) There is nothing that can be translated as "that" in the Greek source. It was added because the previous verb was translated as active rather than a participle.

sent -- (WF) "Sent" is from a Greek verb that means "send," "send forth," "send away," "conduct," and "escort." This is the second most common word Jesus uses that is translated as "send," but this one doesn't have the prefix that has the sense of "out." The form is a participle, introduced by a definite article, "the one sending."

me. -- "Me" is the regular first-person pronoun in Greek as the object of the verb or preposition.