SOURCE: The following Latin translations of Syntipas's Greek fables are by Christian Frederick Matthaei and were published in 1781; the book is available at GoogleBooks. This is fable 19 in Syntipas. For other versions, see Perry 406.
READ OUT LOUD. Choose which marked text you prefer to practice with - macrons or accent marks - and read the text out loud until you feel comfortable and confident. Then, try reading the unmarked text at the bottom. It should be easy for you after practicing with the marked texts. :-)
MACRONS. Here is the text with macrons:
Pellem leōnis repererant canēs eamque lacerābant dentibus. Quōs vidēns vulpes, sīc eōs allocūta esse fertur: "Leo iste, sī adhuc in vīvīs esset, experīrēminī unguēs eius fortiōrēs vestrīs dentibus."
ACCENT MARKS. Here is the text with ecclesiastical accents, plus some color-coding for the words of three or more syllables (blue: penultimate stress; red: antepenultimate stress):
Pellem leónis repérerant canes eámque lacerábant déntibus. Quos videns vulpes, sic eos allocúta esse fertur: "Leo iste, si adhuc in vivis esset, experirémini ungues eius fortióres vestris déntibus."
UNMARKED TEXT. Here is the unmarked text - after practicing with the marked text that you prefer, you should not have any trouble with the unmarked text:
Pellem leonis repererant
eamque lacerabant dentibus.
sic eos allocuta esse
si adhuc in vivis esset,
fortiores vestris dentibus."
IMAGE. Here is an illustration for the story (image source), showing Heracles holding one of the most famous lion skins in antiquity - the skin of the Nemean Lion!