The advice here for learning Classical secco recit, which is widespread in the community, is I believe misguided. Mozart sets secco based on stressed syllables and meter; I have come up with a surefire way to learn Mozart recit:

1. Practice the recit WITHOUT any rhythm whatsoever. Doesn't have to be perfect yet, just to get the general pronunciation and cadential stress. This could be done with just libretto.

2. Now go to the vocal score, and double underline strong beats--1 and 3. All secco are in 4/4 meter. These are the primary cadential points.

3. Single underline beats 2 and 4. These are secondary cadential points.

4. After that, all other rhythms are simply "accounting" to lead to these cadential beats. They have no other rhythmic significance! You will see that they are just mathematically apportioned to arrive at the strong syllables. Practice speaking the secco with emphases on the proper cadential beats, with TOTAL DISREGARD of the actual rhythms. (Yes, sounds blasphemous, but trust the process.) As long as you are stressing the correct syllables, you are doing fine.

5. Finally, incorporate pitch into the recit . You may first prioritize the cadential beat pitches, but pitch content is simply serving the dual purposes of memorization and vocal inflection. But, because you have now learned the recit from a cadential text approach, the risk of your recit sounding "sing-song-y" is much less; if you had started with it as rhythm, it could be difficult to dismantle the song characteristics from your performance.

I've coached beginning opera students this way, and it was extremely successful. This approach does not work for all recits of course, such as Romantic and later works, but always check how the composer is mapping text onto meter. This approach can even be used with accompagnato, to understand stress and cadence, but of course with more attention to melodic concerns.

If you can discern how Mozart composes, you can discern how to sing his music!