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:
Tabula ōlim mōnstrābātur, in quā artifex leōnem immānem ab ūnō homine interfectum pīnxerat. Spectātōrēs cum dē illā stultē glōriārentur, leō quidam praeteriēns "Vōbīs sānē," inquit, "hanc victōriam dat pictor iste; sed solitā fingendī licentiā vōs dēcēpit. Quō certius nōs victōrēs essēmus, sī contubernālēs meī pingere scīrent."
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):
Tábula olim monstrabátur, in qua ártifex leónem immánem ab uno hómine interféctum pínxerat. Spectatóres cum de illa stulte gloriaréntur, leo quidam praetériens "Vobis sane," inquit, "hanc victóriam dat pictor iste; sed sólita fingéndi licéntia vos decépit. Quo cértius nos victóres essémus, si contubernáles mei píngere scirent."
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; I've inserted spaces between the segments to make it easier to follow:
Tabula olim monstrabatur,
in qua artifex
leonem immanem
ab uno homine interfectum pinxerat.
Spectatores cum de illa stulte gloriarentur,
leo quidam praeteriens
"Vobis sane," inquit,
"hanc victoriam
dat pictor iste;
sed solita fingendi licentia
vos decepit.
Quo certius
nos
victores essemus,
si contubernales mei
pingere scirent."
IMAGE. Here is the illustration of the fable by Aractingy:
