But -- (CW) The Greek word translated here as "but" is not the common conjunctions used to mean "but." He usually uses two other words to mean "but." The primary meaning of the word used here is "except" or "save."

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

say- The "say" is one of the common verbs that means "to say" or "to tell." 

unto -- This word "unto" comes from the dative case of the following word that requires the addition of a preposition in English. The most common is a "to" for the English indirect object.

you,  - The "you" here is plural, indicating many of Christ's listeners, which is normal with this phrase.

It  - -- This is from the third-person, singular form of the verb.

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

be  - The "it shall be" verb here is the common form of "to be" in Greek. It means to have a certain characteristic or remain in a certain condition. It is singular and the future tense.

more tolerable - "More tolerable" is the comparative form ("more") of an adjective which "bearable" or "sufferable."

for -- This word "for" comes from the dative case of the following word that requires the addition of a preposition in English. The most common is a "to" for the English indirect object. However, the translator can choose another prepositions: "with,"  "in,"   "of,"  "as," "by," "for," "at," or "on" depending on the context.

Tyre -- This is from the Greek name of the historical city.

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

Sidon -- This is from the Greek name of the historical city.

at  -- The word translated as "at" means "in," "within," "with," "during" (time), or "among"  with a dative object as the one here. 

the -- (IW) There is nothing that can be translated as "the" in the Greek source. There is no indefinite article in Greek, but when a word doesn't have a definite article, the indefinite article can be added in English translation.

day The Greek word translated as "day" also means "time," in general, and specifically to the "daytime."

of - This word "of"  comes from the genitive case of the following word that requires the addition of a preposition in English.  The most common is the "of" of possession.

judgment,  - (CW) The Greek word translated as "judgment" means distinguishing among choices and "separating" things. Christ uses it in a variety of ways, though the KJV usually translates it as "judgment." It also means a "turning point," since it is the source of the meaning of "crisis" has in English. Only secondarily does it means "judgment" as in a court judgment. This Greek word (krisis) is the source of our word "crisis" in the sense that a "crisis" is a time of choosing or a separation. 

than -- "Than" is translated from a Greek word that means primarily "or" but serves as "than" in a comparisons.

for -- This word "for" comes from the dative case of the following word that requires the addition of a preposition in English. The most common is a "to" for the English indirect object. However, the translator can chose another prepositions: "with,"  "in,"   "of,"  "as," "by," "for," "at," or "on" depending on the context.

you.  - The "you" here is plural, indicating many of Christ's listeners.