原：The elephant's tail is long and thin汉：大象的尾巴是长的又瘦的
改：The elephant's tail is isn't long isn't thin汉：大象的尾巴是不长不瘦的√
The elephant's tail isn't short nor bulky.汉：大象的尾巴不短也不笨×
The elephant's tail isn't short or thick. 汉：大象的尾巴不短或厚×