Lot of interesting words here and lots of meanings lost in translation. So much here that it is hard to summarize. There are also two unique words for Jesus, including one that appears no where else in Greek literature.  There are untranslated words here and words added that are not in the Greek.

This verse is clear proof that, when Jesus's words were recorded, some of the questions and comments of others were left out. Simon is addressed here for some reason, almost certainly because he made a comment or asked a question, but that comment of question was not recorded. We know that this statement wasn't made just about him personally, however, because the "you" here is plural.   It is a good example of how the plural "you" in Greek is easily confused with the singular "you" in English.

"Simon" is assumed to be a Hebrew name. Strangely enough, the word also has a meaning in Greek, it is a verb that means "turning up a nose" and this form could also be the noun, "flat nose" or adjective, "snub-nosed". It also means, interestingly, "a confederate in evil", given the context of "satan" here. The name only appears in the New Testament, where it occurs an astounding twelve times. This is interesting given that everyone there would recognized the word's Greek meaning. There is also something very entertaining about a man named "Flat-nose" being renamed "Rocky."  However, the source question that Jesus is answered could have also been Simon the Zealot, another of the apostles.

"Behold" is a verbal command meaning "See!" and "Look!" It is from the most common word meaning "to see" in Greek. In a humorous vein, it is also an adverbial exclamation like we use the phrase "tah-dah" in a magic show, or "voila" in French. "Look!" or "See!" comes closest in English. Jesus uses it both ways.

The untranslated word here is the Greek definite article, which usually precedes a noun and, without a noun, takes the meaning of "the one." Here, however, it comes in front of a noun, the next word. The Greek article is much closer to our demonstrative pronouns ("this", "that", "these", "those"). See this article for more. 

"Satan" is from an Aramaic word meaning "adversary" or "opponent". It is preceded by an article, so "the adversary." See this article on the word and this article on this word and related terms. 

"Hath desired" is a Greek verb that only appears here and means to "demand or ask for (from another) and "demand the surrender" of a person. In the middle voice, which is used here, it means to "ask for oneself", "beg of", "gain" (a pardon), and "release." It does not mean "desire" in any normal sense and there are common words that Jesus uses that mean "desire". When Jesus uses specific word like this, it is because it has a meaning no other word has. For this word, the idea is that it demands a transfer of control.

There is no Greek that means "to have" you in this verse. It is added to clarify the meaning of the previous verb, since that verb suggests a transfer. 

The "you" here is plural. So Jesus is not saying this about Simon personally but about all of his apostles. .

"That he may sift" is from a verb that means "to winnow" or "to sift". This verb is found nowhere else in ancient Greek literature, but it is easy to define because it is a verb form of the Greek word for "sieve" and the context of "wheat". The form, however, is interesting. It is a verb in the form of an infinitive that is preceded by an article ("the"). This is the Greek way of creating a noun describing the action. We do the same thing in English but with gerunds not infinitives.  So "eating" becomes the noun describing the action of eating. "the eating of a meal". Here, "to shift" becomes "the sifting of the wheat".

There is no "you" here in the Greek, but objects in Greek are often used once and assumed later in the sentence.

The word translated as "as" has a very broad meaning, translating as "how", "when", "where", "just as", "like," and related words.

"Wheat" is from the Greek noun that means "grain", "wheat", "barley", "food made from grain", "bread," and, most generally, "food."