VOA慢速英语:Personal Flying Vehicles Close to Reality

overlap – v. to lie over the edge of something; to cover part of something

propeller – n. a device with two or more blades that turn quickly and cause a ship or aircraft to move

prototype – n. an original or first model of something from which other forms are copied or developed

fold – v. to place one part over another; to tie together

pack – v. to put away

rotor – n. a part of a machine that turns around a central point

reliability – n. the ability to depend on someone or something