Thought is the past tense (e.g., “Lenka thought it was easy”) and past participle (e.g., “Garth simply hadn’t thought of that”) of the verb think. It is also an abstract noun. So, when we think, we can be said to “have thoughts.”
Think is an irregular verb, so it doesn’t add “-ed” to form the past tense.
Use the QuillBot Grammar Checker to make sure your use of the past tense of think is correct.