Students get a more difficult lesson than they expected when instructor Cardi B lets loose in a new spot from streaming service Spotify, which finally went public last week.

In the 45-second TV spot Cardi's landed herself a position at a stuffy music conservatory. (Adjunct? Tenure-track?) But rather than stick to the classics, she instructs the class in a round of her signature, lively ad-libs. While those are easy enough to replicate, the students are dumbstruck when she hits them with a full verse. It's a bit of a departure from the streaming service's previous work, which has leaned heavily into data riffing off the listening habits of its userbase, like in its holiday campaign that had fun with Ed Sheeran being 2017's most-streamed artist.

In the new ad, the platform focuses primarily on the Bronx-born rapper herself, who on Friday dropped her debut studio album "Invasion of Privacy" and made it available to stream on Spotify. The next day, after months of media speculation, she went public with her pregnancy during the broadcast of "Saturday Night Live," during which the spot made its one-time TV appearance.