tiresome/tiring/tired

My books that a short time ago had seemed so tiresome,so heavy to carry,now seemed to me like old friends.我那些课本刚才还那么讨厌，携带起来还姥沉重，现在它们却好象是我的老朋友了。
We never thought the climb was so tiring.我们从没想起登山会使人这样疲劳。
I thought that the ants would be tired from their day-long work.我认为这些蚂蚁会因为成天劳动而累了。
<辨析>这三个都是形容词。tiresome 与 tiring 均可表示“使人疲劳的”、“令人讨厌的”，两者一般可互换。tired 意为“（人）感到疲劳的”、“（人）感到厌烦的”。试比较：The lecture lasted no less than five hours and everyone was tired.演讲长达5小时之久，人人都感到疲倦了。The lecture lasted on less than five hours and the lecturer was really tiresome (tiring).演讲长达5小时之久，而这位演讲人又实在叫人厌倦。