The past tense of the verb ‘know’ is ‘knew’. This irregular verb does not follow the standard rule of adding ‘-ed’ to form its past tense.
To understand why we use ‘knew’, it’s important to recognize the way some verbs in English change their spelling when moving from present to past tense. ‘Know’ is one of those verbs that changes entirely. For example, other irregular verbs include ‘go,’ which becomes ‘went’ in the past tense.
Here’s an example of how to use ‘knew’ in a sentence: ‘Yesterday, I knew the answer to the question, but today I’m not so sure.’ This demonstrates not only the correct use of the past tense but also provides context to its meaning.