38 Here καί (kai) has been translated as “then” to indicate the implied sequence of events within the vision.
39 The Greek article τήν (tēn) has been translated with demonstrative force here.
40 The Greek term καί (kai) has not been translated here and before the following term “month” since English normally uses a coordinating conjunction only between the last two elements in a series of three or more.
41 Grk “so that they might kill,” but the English infinitive is an equivalent construction to indicate purpose here.

In other versions

So the four angels, who had been prepared for the hour, the day, the month, and the year, were released to kill a third of mankind.

And the four angels who had been kept ready for this very hour and day and month and year were released to kill a third of mankind.

So the four angels who were prepared for the hour, day, month, and year were released to kill a third of the human race.

Then the four angels who had been prepared for this hour and day and month and year were turned loose to kill one-third of all the people on earth.

And the four angels who had been prepared for the hour and day and month and year were released, in order that they should kill a third of humanity.

And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men.

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