This is an item from Anton Moker's Decalogus metricus et paraenetica disticha, published in 1573. You can see the book at GoogleBooks.
Tempus Irrevocabile
Utere temporibus: volat irrevocabile tempus;
Atque stude, quia non quae fuit hora redit.
The vocabulary is keyed to the DCC Latin Vocabulary list. There are two words in this poem that are not on the DCC list:
irrevocābilis, -e (irrevocābilis): irrevocable
volō, volāre: fly
atque, ac: and in addition, and also, and; (after comparatives) than; simul atque, as soon as
hōra -ae f.: hour
nōn: not
qui quae quod: who, which, what / quis quid: who? what? which?
quia: because
redeō -īre -iī -itum: go back, return
studeō -ēre -uī: be eager, be zealous, care for (+ dat.)
sum, esse, fuī: be, exist
tempus -oris n.: time
ūtor ūtī ūsus sum: use
