"a foolproof identification system" "the unfailing sign of an amateur" "an unfailing test"
"an unfailing source of good stories" "a subject of unfailing interest"
"unfailing loyalty" "unfailing good spirits" "unflagging courtesy"
unfailing是什么意思
unfailingly是什么意思
unfair是什么意思
unfaithful是什么意思
unfaithfully是什么意思
unfalsifiable是什么意思
unfaltering是什么意思
unfamiliar是什么意思
unfamous是什么意思
unfancy是什么意思