Hi Luna Thought is past tense. So phrases 1 and 3 are correct. Please feel free to message me if I can help you further.

Hey Luna. If you want to use the word "thought," then (1) and (3) are correct for the past tense. Just some extra information, if you would like to change sentences (2) and (4) to present tense, you should change the word "thought" to "think." Hope this helps.

The difference between give back and take back is with give back it means you volunteered to give back something. Whereas take back would be it was involuntary taken back by someone or you accepted something back from someone if it was given to you.