Der Freischütz, Op. 77, J. 277, (usually translated as The Marksman or The Freeshooter) is a German opera with spoken dialogue in three acts by Carl Maria von Weber with a libretto by Friedrich Kind. It premiered on 18 June 1821 at the Schauspielhaus Berlin. It is considered the first important German Romantic opera, especially in its national identity and stark emotionality.

The plot is based on the German folk legend of the Freischütz and many of its tunes were thought to be inspired by German folk music, but this is a common misconception. Its unearthly portrayal of the supernatural in the famous Wolf’s Glen scene has been described as “the most expressive rendering of the gruesome that is to be found in a musical score”.

https://en.wikipedia.org/wiki/Der_Freisch%C3%BCtz

https://en.wikipedia.org/wiki/Le_devin_du_village

https://en.wikipedia.org/wiki/Jean-Jacques_Rousseau

In classical music, arioso [aˈrjoːzo] (also aria parlante^[1] [ˈaːrja parˈlante]) is a type of solo vocal piece, usually occurring in an opera or oratorio, falling somewhere between recitative and aria in style. Literally, arioso means airy. The term arose in the 16th century along with the aforementioned styles and monody. It is commonly confused with recitativo accompagnato.

Arioso is similar to recitative due to its unrestrained structure and inflexions, close to those of speech. It differs, however, in its rhythm. Arioso is similar to aria in its melodic form, both being closer to singing than recitative; however, they differ in form, arioso generally not resorting to the process of repetition.

https://en.wikipedia.org/wiki/Arioso

Pietro Antonio Domenico Trapassi, better known by his pseudonym of Pietro Metastasio (Italian pronunciation: [metaˈstaːzjo]; 3 January 1698 – 12 April 1782), was an Italian poet and librettist, considered the most important writer of opera seria libretti.

https://en.wikipedia.org/wiki/Pietro_Metastasio

Arias became classifed into standard types. There are many different types,
including the fve we will describe here. First, the aria cantabile showcases
all of the singer’s lyrical ability. The aria di portamento is a dignifed aria
designed to show off the singer’s breath and tone control. The aria di mezzo
caratere is a compromise between the aria cantabile and the aria di bravura.
The aria parlante (patter aria) demonstrates the singer’s agility, and the aria
di bravura (or aria d’agilità) is highly forid and designed to show off the
singer’s agility and extraordinary vocal compass.