Know - no

The two homophones know and no IPA: /nəʊ/should never be confused, though tired writers - and children learning to write - have been known to confuse them.

• The verb 'to know' means 'to have knowledge'. (The mnemonic that the k- is next in the alphabet to the l- of 'to learn' may help some.) 'To know' is an irregular verb whose forms are given at know.
• No may be a noun, and adjective, an adverb or an interjection. In all of these word classes, its meaning is purely negative.

See also knew - new.