形容詞 colorless:

1. lacking in variety and interest
   同義詞：colourless
2. weak in color; not colorful
   同義詞：colourless

1. Ammonia is a colorless gas with strong smell.
   氨是無色并有強(qiáng)烈氣味的氣體。
2. Glycerin is a thick sweet colorless liquid.
   甘油是一種很甜且無色的濃稠液體。
3. He has become colorless because of anger.
   他因?yàn)樯鷼?，臉色蒼白。
4. Water is colorless.
   水是無色的。
5. The old man's life became dull and colorless.
   老人的生活變得呆板無趣。

col.or.less

adj.（形容詞）
Lacking color.
缺色的
Weak in color; pallid.
色弱的；蒼白的
Lacking animation, variety, or distinction; dull.See Synonyms at dull
無精打彩的，乏味的：缺少生氣、變化或差別的；乏味的參見 dull

【引伸】
col.orlessly
adv.（副詞）
col.orlessness
n.（名詞）