READ OUT LOUD. Choose which marked text you prefer to practice with - macrons in verse form, or macrons in prose order, or accent marks in prose order, or focusing on the meter. You will find materials for all of these options below. :-)
VERSE MACRONS. Here is the verse text with macrons:
In stabulīs faenī plēnīs Canis incubat ācer;
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Prōtinus hunc saevīs prohibet lātrātibus ille;
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Bōs ait īrātus, "Tē perdant, invide, Dīvī!
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PROSE MACRONS. Here is the same text with macrons written out in prose word order:
Canis ācer incubat in stabulīs faenī plēnīs. Ecce! Taurus adest, pābula comēsūrus. Prōtinus Canis lātrātibus saevīs Taurum prohibet, et non sinit Bovem, impāstum, līmen adīre. Bōs, īrātus, ait: "Dīvī tē perdant, invide! Tu ipse vēscī nequīs, et mē cibō prohibēs.
STRESS (ACCENT) MARKS. Here is the prose text with accents, plus some color-coding for the words of three or more syllables (blue: penultimate stress; red: antepenultimate stress):
Canis acer íncubat in stábulis faeni plenis. Ecce! Taurus adest, pábula comesúrus. Prótinus Canis latrátibus saevis Taurum próhibet, et non sinit Bovem, impástum, limen adíre. Bos, irátus, ait: "Divi te perdant, ínvide! Tu ipse vesci nequis, et me cibo próhibes."
ELEGIAC COUPLET METER. Below I have used an interpunct dot · to indicate the metrical elements in each line, and a double line || to indicate the hemistichs of the pentameter line.
In stabu·līs fae·nī plē·nīs Canis· incubat· ācer;
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Prōtinus· hunc sae·vīs prohi·bet lā·trātibus· ille;
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Bōs ait· īrā·tus, Tē· perdant,· invide,· Dīvī!
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IMAGE. Here is the illustration of the "dog in the manger" (image source) by Walter Crane:
What follows is an unmarked version of the prose rendering to faciliate word searches: Canis acer incubat in stabulis faeni plenis. Ecce! Taurus adest, pabula comesurus. Protinus Canis latratibus saevis Taurum prohibet, et non sinit Bovem, impastum, limen adire. Bos, iratus, ait: "Divi te perdant, invide! Tu ipse vesci nequis, et me cibo prohibes.