dull

dull, tedious, monotonous, dreary

这些形容词均表示“单调的、乏味的、厌烦的”之意。
dull: 指缺乏新鲜、吸引力或情趣而显得乏味、沉闷。
tedious: 侧重指文章、演讲、演出等冗长乏味或环境等单调、沉闷，缺乏活力，使感到不舒服。
monotonous: 指没有变化、重复单调的。
dreary: 侧重无趣味的，不活泼的事或思想状态。

动词 dull:

1. make dull in appearance
2. become dull or lusterless in appearance; lose shine or brightness
3. deaden (a sound or noise), especially by wrapping
   同义词：muffle, mute, damp, dampen, tone down
4. make numb or insensitive
   同义词：numb, benumb, blunt
5. make dull or blunt
   同义词：blunt
6. become less interesting or attractive
   同义词：pall
7. make less lively or vigorous

形容词 dull:

1. lacking in liveliness or animation
2. emitting or reflecting very little light
3. being or made softer or less loud or clear
   同义词：muffled, muted, softened
4. so lacking in interest as to cause mental weariness
   同义词：boring, deadening, ho-hum, irksome, slow, tedious, tiresome, wearisome
5. (of color) very low in saturation; highly diluted
6. not keenly felt
7. slow to learn or understand; lacking intellectual acuity
   同义词：dense, dim, dumb, obtuse, slow
8. (of business) not active or brisk
   同义词：slow, sluggish
9. not having a sharp edge or point
10. blunted in responsiveness or sensibility- Willa Cather
11. not clear and resonant; sounding as if striking with or against something relatively soft
    同义词：thudding
12. darkened with overcast
    同义词：grey, gray, leaden

1. He felt a dull ache in his shoulder.
   他感到肩膀隐隐作痛。
2. This student is very dull.
   这个学生非常愚钝。
3. It's impossible to cut a pineapple with such a dull knife.
   用一把这么钝的刀子切菠萝是不可能的。
4. This book is rather dull.
   这本书很枯燥。