câu 1:You/Music//How to sing and play the piano

     => What do you study in music?                                                                 

      => In music , i study how to sing and play the piano                                                               

2.Lan/History//past events in Viet Nam and around the world 

       => What does Lan study in History ?
In history , she studies about past events in VN and around the world              

3.They/English//how to speak ,listen read and write in English

        => What do they study in English?                                                                   

NHỚ CHO MÌNH CÂU TRẢ LỜI HAY NHẤT NHÉ 

`II.`

`1. =>` What do you learn in music?

ANS: I learn how to sing and play the piano.

`2. =>` What does Lan learn in History?

ANS: She learns about past events in VN and around the world

`3. ->` What do they learn in English?

ANS: They learn how to speak, listen, read and write in English. 

- Form: Wh-questions + do/does + S + V-inf + ...?

ANS: S + V(s/es) + ...

- how + to V-inf: cách để làm gì...