NoDictionaries.com: You can find the word list for this fable online, and use it interactively (here are some tips on how to make best use of the tool).
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:
Iūppiter, cum avibus rēgem daturus esset, diem constituit, quā convenīrent ad ipsum. Tum graculus, suae sibi dēformitātis conscius, pennās, quae aliīs avibus exciderant, sustulit iīsque ornātus prōcessit. Cēterae autem avēs suas quaeque pennās impudentī illī ēripuērunt atque dērīsum rōstrīs fugāvērunt.
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):
Iúppiter, cum ávibus regem datúrus esset, diem constítuit, qua convenírent ad ipsum. Tum gráculus, suae sibi deformitátis cónscius, pennas, quae áliis ávibus excíderant, sústulit iísque ornátus procéssit. Céterae autem aves suas quaeque pennas impudénti illi eripuérunt atque derísum rostris fugavérunt.
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:
Iuppiter,
cum
avibus regem daturus esset,
diem constituit,
qua convenirent ad ipsum.
Tum graculus,
suae sibi deformitatis conscius,
pennas,
quae aliis avibus exciderant,
sustulit
iisque ornatus
processit.
Ceterae autem aves
suas quaeque pennas
impudenti illi eripuerunt
atque derisum
rostris fugaverunt.
IMAGE. Here is an illustration for the story (image source) from a 15th-century edition of Aesop's fables:
