A UAV is a flying machine with no pilot inside it. Someone controls it from the ground, or it flies itself by following a plan and using GPS. The letters stand for Unmanned Aerial Vehicle.

A UAV一台UAV is a flying machine是一種飛行器 with no pilot inside it裡面沒有駕駛員。Someone controls it有人在地面 from the ground操控它 or或 it flies itself它自己飛 by following a plan and using GPS靠著預先設定的計畫和GPS。The letters stand for這幾個字母代表 Unmanned Aerial Vehicle「Unmanned Aerial Vehicle」（無人飛行載具）。

The everyday word for the same thing is 'drone' — that is what almost everyone says in normal talk. 'UAV' is the formal word: you meet it in the army, in engineering reports, in news about war, and in rules made by governments. So a soldier's report says UAV; a shop selling one to you says drone.

The everyday word for the same thing日常說法 is 'drone'是「drone」 that is what almost everyone says in normal talk一般人講話幾乎都用這個字。'UAV' is the formal word「UAV」是正式用詞 : you meet it你會在 in the army軍隊裡 in engineering reports工程報告裡 in news about war戰爭新聞裡 and和 in rules made by governments政府訂的法規裡 碰到它。So a soldier's report所以軍人的報告會 says UAV寫UAV a shop selling one to you但賣給你的店家會 says drone說drone。

UAVs range from a small four-propeller toy you hold in one hand, up to a machine as big as a real plane. They are used to look at things from above — watching an area, taking photographs, mapping land, checking crops or power lines — and some military ones also carry weapons.

UAVs range from一台UAV可以小到 a small four-propeller toy you hold in one hand你單手拿著的四旋翼小玩具 up to一直大到 a machine as big as a real plane跟真飛機一樣大的機器。They are used to它們被用來 look at things from above從上空觀察東西 watching an area監看一個區域 taking photographs拍照 mapping land測繪土地 checking crops or power lines檢查農作物或電線 and而且 some military ones also carry weapons有些軍用款還會攜帶武器。

You say the three letters separately: U-A-V. It is a countable noun: one UAV, two UAVs.

You say the three letters separately要把三個字母分開唸 : U-A-VU-A-V。It is a countable noun它是可數名詞 : one UAV, two UAVsone UAV、two UAVs 這樣數。

You will also meet 'UAS' (Unmanned Aircraft System), which means the aircraft plus the controller and the ground equipment all together, and some official writing now prefers 'uncrewed' to 'unmanned'.

You will also meet你還會碰到 'UAS' (Unmanned Aircraft System)「UAS」（Unmanned Aircraft System） which means它指的是 the aircraft plus the controller and the ground equipment all together飛機加上操控器和地面設備全部加在一起 and而 some official writing now prefers現在有些官方文件比較愛用 'uncrewed' to 'unmanned'「uncrewed」而不是「unmanned」。