1. "Have astronomers discovered any planets similar to Earth?" 

=> Dean asked his father ______________any planets similar to Earth

2. "Have scientists found water on Mars?"

=> Tom asked his teacher _________water on Mars

`1.` Dean asked his father if astronmers had discovered any planets similar to Earth.

`-` Câu tường thuật : S + asked + O + if + S + V(lùi thì)

`-` Lùi thì : HTHT `->` QKHT

`-` tobe similar to sth : giống với cái gì

`2.` Tom asked his tracher if scientists had found water on Mars.

`-` Câu tường thuật : S + asked + O + if + S + V(lùi thì)

`-` Lùi thì : HTHT `->` QKHT

`1`.Dean asked his father if astronomers had discovered any planets similar to Earth.

`2`. Tom asked his teacher if scientists had found water on Mars.

`@` cấu trúc chung

`-` S + say(s)/said hoặc tell/told + (that) + S + V

`-`S + asked/wanted to know/wondered + if/whether + S + V

`-`S + asked (+O)/wanted to know/wondered + Wh-words + S + V.

`-`S + told + O + to-infinitive.