The noun "quality" can be both countable and uncountable.
Meaning: the standard of something, or how good it is
Example sentence: Products of high quality are usually more expensive than products of low quality.
Meaning: a particular feature of someone or something
Example sentence: Jenny's best qualities are her kindness and her willingness to help other people.
Test your understanding:
- Einstein's intelligence was of the highest quality.
- Einstein's greatest quality was his intelligence.