characterized by extreme care and great effort; "conscientious application to the work at hand"; "painstaking research"; "scrupulous attention to details"
guided by or in accordance with conscience or sense of right and wrong; "a conscientious decision to speak out about injustice"
ask (someone) to marry you; "he popped the question on Sunday night"; "she proposed marriage to the man she had known for only two months"; "The old bachelor finally declared himself to the young woman"