【单选题】Ihave never seen such a strange animal _______ 3 legs like that.
【单选题】I have never seen ______ little birds eat ______ many insects in ______ a short time. [ ]
【单选题】I have never seen to lose any weight, _____hard I try. [ ]
【单选题】Dinosaurs have completely died out on the earth, never again. A . to be seen B . being seen C . seen D . seen