The audio here is generated speech. A recorded human voice for this lesson is on the way.
The sound
For L, the tongue tip rests on the ridge behind your top teeth while the air flows out around both sides. The tip stays in contact the whole time; that contact is what separates L from R, where the tongue touches nothing.
English has two flavors of L. At the start of a word, "light" and "love", it is clear and bright. At the end of a word or before a consonant, "ball", "milk", "feel", it is dark, with the back of the tongue pulled up, almost like a soft "ul". Americans use the dark L a lot, and hearing it helps you understand fast speech.
Hear the difference
Tap each word. Then test your ear.
L: tongue tip touches. R: tongue touches nothing.
Say it out loud
Tap a sentence to hear it. Say it after the voice.
Final L in "I'll", "call" and "all" is the dark, soft kind.
Practice · 3 min
Repeat each sentence, keeping your tongue tip touching on every L. Then record "light, right, long, wrong" and check that the pairs sound different when you listen back.
Say it today
Use it once in a real conversation before tomorrow. Out loud counts, even to yourself.