After the first few words, this verse in Greek is a string for verbs and conjunctions. The first phrase is a good example of natural Greek word order, where all the keywords come before the details. And it contains a word that Jesus only uses once.  This verse's vocabulary is repeated again in Luke 15:32. 

The Greek source of "for" is a word that means "that" or "because.

"This" is translated from a Greek word that means "this", "that", "the nearer." -- The word translated in KJV as "thus" is in its adverbial form, so it means "in this manner" or "in this way."

"My" is the first-person possessive singular pronoun. 

The word translated as "son" more generally means "child" or "children". 

The verb "was" 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.   

The word translated as " dead" means "dead", "corpse", "a dying man," and "inanimate, non-organic matter." Christ uses it in all three senses, referring to the actual dead, the spiritually dead, and inanimate matter.  

The Greek word translated as "and" is used as the conjunction "and", but it also is used to add emphasis ("also"). 

"Alive again" is a Greek verb Jesus only uses here and in a later verse in this story. It  means to "return to life" and "be alive again."

The verb "was" 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. 

The word translated as "Lost" means to destroy or demolish. It can also mean "to lose."  Jesus often uses it as the opposite of "found" so "lost". It is the form of an adjective, "being lost". However, it is not passive, so "having lost." 

The Greek word translated as "and" is used as the conjunction "and", but it also is used to add emphasis ("also"). 

The term used for "is found" is the source of our word, "heuristic," meaning enabling a person to find out something for themselves. It means "find out" and "discover."  It is a passive verb. 

The Greek word translated as "and" is used as the conjunction "and", but it also is used to add emphasis ("also"). 

"They began" is from a verb in the form of an adjective that means "to be first", "to begin," and "to make a beginning", "to rule", "to govern," and "to command."  The two meanings, "to start" and "to command" create different meanings when paired with the following verbs.  The form is someone acting on themselves, so "make a start for yourself" or "command yourself". 

The Greek verb translated as  "to be merry" means "cheer", "gladden", and in the passive, "make merry", "enjoy oneself". Used commonly in parables by Luke, specifically in the parable of the prodigal son. It is also used in the parable of Lazarus and the man building the warehouse. These three parables have a lot of uncommon features for Jesus's parables and this word is one of them.  It is in the form of an infinitive.