  Owing to the recent identification of major substructures in our Milky Way
(MW), the astronomical community has started to reevaluate the importance of
dissolved and existing dwarf galaxies. In this work, we investigate up to 13
elements in 43 giant stars of the Sculptor dwarf galaxy (Scl) using
high-signal-to-noise-ratio near-infrared (NIR) APOGEE spectra. Thanks to the
strong feature lines in the NIR, we were able to determine high-resolution O,
Si, and Al abundances for a large group of sample stars for the first time in
Scl. By comparing the [$\alpha$/Fe] (i.e., O, Mg, Si, Ca, and Ti) of the stars
in Scl, Sagittarius, and the MW, we confirm the general trend that less massive
galaxies tend to show lower [$\alpha$/Fe]. The low [Al/Fe] ($\sim -0.5$) in Scl
demonstrates the value of this ratio as a discriminator with which to identify
stars born in dwarf galaxies (from MW field stars). A chemical-evolution model
suggests that Scl has a top-light initial mass function (IMF), with a high-mass
IMF power index of $\sim -2.7$, and a minimum Type Ia supernovae delay time of
$\sim 100$ Myr. Furthermore, a linear regression analysis indicates a negative
radial metallicity gradient and positive radial gradients for [Mg/Fe] and
[Ca/Fe], in qualitative agreement with the outside-in formation scenario.
