大尉【たいい】
captain (Army, US Marine Corps, USAF), lieutenant (Navy), flight lieutenant (RAF, RAAF, RNZAF, etc.)
中尉【ちゅうい】
first lieutenant, lieutenant junior grade
少尉【しょうい】
second lieutenant, sublieutenant, ensign
一尉【いちい】
captain (JASDF, JGSDF), lieutenant (senior grade; JMSDF)