n. 管子, 导管；管状虫；伦敦地铁（tube的复数）

n conduit consisting of a long hollow object (usually cylindrical) used to hold and conduct objects or liquids or gases

n electronic device consisting of a system of electrodes arranged in an evacuated glass or metal envelope

n a hollow cylindrical shape

n (anatomy) any hollow cylindrical body structure

n an electric railway operating below the surface of the ground (usually in a city)

v provide with a tube or insert a tube into

v convey in a tube

v ride or float on an inflated tube

v place or enclose in a tube