Câu tường thuật - dạng Wh-questions 

S + asked / wanted to know / wondered + (O) +WH + S+ V (lùi thì)

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Đáp án: Lan asked Hung where he was going on vacation the next summer.

HTTD --> QKTD

next summer --> the next summer / the following summer. 

`color{orange}{~MiaMB~}`

`->` Lan asked Hung where he was going on vaction the following summer

`-` Lùi thì : HTTD `->` QKTD

`-` Đổi ngôi : you `->` he

`-` Đổi thời gian : next summer `->` the following summer

`-` GT - Wh-questions : S + asked (+ O)/wanted to know/wondered + Wh-questions + S + V(lùi thì/đổi ngôi)