They refers back to “those who are invited” at the beginning of verse 4; Good News Translation identifies they through the use of the phrase “the invited guests.”

Made light of appears in Good News Translation and Moffatt as “paid no attention”; New English Bible, An American Translation, and Phillips have “took no notice of”; New Jerusalem Bible has “they were not interested”; New American Bible has the one word “ignored.” Elsewhere in the New Testament, the verb is used in 1 Timothy 4.14; Hebrews 2.3; 8.9. The verb can also be rendered “disregarded” or “did not take seriously.” It may need to be replaced by “the invitation.”

Went off, one to his farm, another to his business is considerably restructured in Good News Translation: “went about their business: one went to his farm, another to his store.” It will also be acceptable to say “went somewhere else. Some went to the farms, others to their businesses.”

One … another is probably best taken in a collective sense: “some went to their farms, others went to their place of business.” Business (Good News Translation, Die Bibel im heutigen Deutsch “store”) or “trade” is the primary meaning of the noun, which occurs nowhere else in the New Testament; a related noun occurs in John 2.16.

Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .