* Descriptive: "The diver strapped on his aqualung and plunged into the crystal-clear water."
* As a noun: "The aqualung revolutionized underwater exploration, allowing humans to breathe freely beneath the waves."
* With a verb: "He aqualunged through the coral reef, marveling at the colorful fish."
You can also use "scuba gear" or "SCUBA" as synonyms for "aqualung" in these sentences.