The initial idioms of the letter U

under	under a cloud
under a microscope	under age
under any circumstances	under the circumstances
under attack	under belt
under canvas	under certain circumstances
under consideration	under construction
under cover	under false colors
under foot	under hat
under heel	under (the/someone's) radar
under (one's) very eyes	under lock and key
under no circumstances	under normal circumstances
under nose	under oath
under one's belt	under one's breath
under one's feet	under one's nose
under one's own steam	under own steam