what i have done同 what have i done有咩分別？

These two sentences both mean "我做了什麼?". However, they are different in use.

"What have I done?" is a question. (the verb "have" is placed before subject "I")

"What I have done" is used as a part of sentence or a question.(the verb "have" is placed after subject "I")
For example, "what i have done was just watching TV." ("was" is verb, "what i have done" bocome subject) or "do you know what I have done?" It would be wrong if you say "do you know what have I done?".

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what i have done個 what系１個連接詞"]]
SO what i have done 唔系"
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而what have i done就係１句問題"
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what i have done <--- 成句係relative clause

what 係 relative pronoun

而後面 "i have done" 係一個clause

i 係subject

have done 係 verb



what have i done <--- 成句係一句question

what 係 question word

have 係 auxilary

i 係subject

done 係因為have 的緣故所以do 以 past participle form 出現