ADJ

fine, narrow, thin
broad
hollow
flexible
closed, sealed
inner (= in a bicycle tyre)
fluorescent (= a kind of light)
aluminium, cardboard, copper, glass, metal, plastic, steel
discharge, drainage, suction
test
breathing, feeding, ventilation
capillary, bronchial, Fallopian, neural
London

PREP

down a/the ~
pouring the liquid down the tube
in/into a/the ~
I put the poster back into its tube
through a/the ~
He gave the lamb its food through a tube
up a ~ 2 the tube the Underground
by ~
I go to work by tube
on the ~
I bumped into him on the tube

VERB + TUBE

go on, take, travel by/on

TUBE + NOUN

line, station, ticket, train