2 . On Thursday morning, two teenage boys were rescued by a drone (无人机) in Australia while lifeguards were still training to use the machine.

The ______, aged 15-17, got into difficulties about 700 feet off the coast of Lennox Head, New South Wales (NSW). A passerby saw them ______ in dangerous waves. Lifesavers ______ sent the drone to drop a lifeboat, and the pair made their way safely to the ______.

The drone, known as “Little Pipper”, was actually not ______ to be saving anyone just yet---lifeguards were being trained to ______ the machine. When a call came about the swimmers ______, the drone happened to be nearby.

Jai Sheridan was the lifeguard who ______ the drone. He described the experience as ______. “The Little Ripper ______ proved itself today. It is a highly efficient (高效的) piece of lifesaving equipment. I was ______ the drone when the alarm was raised. I directed it towards the swimmers, and dropped the ______. With its support they made their way to safety. They were ______, but not hurt. The teens were rescued in just 70 seconds with the drone---while a lifeguard would have taken up to six minutes to ______ the rescue.”

John Barilaro, an official of the state, ______ the rescue as historic. “It was the world’s ______ rescue by the unmanned aircraft”, he said. “Never before has a drone been used to ______ swimmers like this.”

Last December, the NSW state government ______ some “Little Ripper” drones for 247,000 pounds. ______ some are designed to spot sharks, others are ______ with lifeboats, alarms and loudspeakers. “It was money well spent,” said John Barilaro.