ugly as sin
   under a cloud
   under construction
   under fire
   under one's own steam
   under someone's nose
   under the circumstances
   under the counter
   under the table
   under the weather
   until all hours
   up a blind alley
   up against
   up and about
   up and at them
   up and doing
   up in arms
   up in the air
   up in years
   up North
   up to date
   up to no good
   up to one
   up to one's ears
   up to one's neck
   up to par
   upper crust
   ups and downs
   upset someone's plans
   upset the applecart
   upshot of
   upside down
   use every trick in the book
   use one's head
   use one's noddle
   use strong language
   used to
   Uncle Sugar
   up for something
   up front
   up the river
   up time
   upper story
   Uncle Tom Cobley and all
   up for it
   up the duff
   uphill gardener
   upstairs gardener
   Ubol Ratchathani
   Ubon Ratchathani University
   Udon Thani
   ugly duckling
   Ulan Bator
   ultrahigh frequency
   ultraviolet ray
   umbilical cord
   umbrella sheath
   unbleached cotton thread
   unboiled water
   Uncle Sam
   Uncle Tom
   uncovered verandah
   undecided case
   underarm odor
   underdeveloped country
   underground resource
   underground tunnel
   underground water
   unidentified flying object
   Union Jack
   Union of Burma
   Union of South Africa
   Union of Soviet Socialist Republics
   unit cell
   United Arab Emirates
   United Arab republic
   United Kingdom
   United Nations
   United Nations Charter
   United States of America
   universal coupling
   universal joint
   upper chamber
   upper class
   upper hand
   upper house
   urban area
   urban renewal
   uric acid
   urinary bladder
   Ursa Major
   Ursa Minor
   utility pole
   unbosom oneself
   unburden oneself
   understand by
   unfit for
   unfold before
   unfold to
   unify into
   unify with
   unite in
   unite with
   unleash on
   unload on
   upbraid for
   upbraid with
   upgrade to
   urge along
   urge on
   urge to
   use as
   use before
   use for
   use to
   use up
   use with
   usher in
   usher out
   utilize for