The sentence you provided is: "The peacock sports brightly coloured feathers, but its singing is quite unpleasant."
The sentence is mostly grammatically correct, but here are a few points to consider:
- "brightly coloured": This is correct in British English. In American English, it would typically be spelled "brightly colored." Both are acceptable depending on the style you are using.
- Comma usage: The comma before "but" is appropriate because it's joining two independent clauses.
- Clarity: The sentence clearly contrasts the peacock's beautiful feathers with its unpleasant singing, which is well expressed.
Possible minor improvement for style: You might say, "The peacock sports brightly coloured feathers, but its call is quite unpleasant." The word "call" is often used to refer to bird sounds and can sound more natural than "singing" for a peacock.
Final suggestion: "The peacock sports brightly coloured feathers, but its call is quite unpleasant." Otherwise, your original sentence is grammatically correct.