`2`

`-` The cave at the end of the beach was near some big, grey rocks at the other.

keywords(thông tin trong bài):  Then Harry saw a strange cave which was near some big, grey rocks at
the other end of the beach.

__________________________________________________________________

`3`

`-` The boys couldn't see inside the cave because it was too dark there.

keywords(thông tin trong bài): he boys quickly ran to it and looked in, but they couldn't see anything because it was very dark

2.some big
Dòng thứ nhất của đoạn 2 (then Harry saw... some big)
3.dark
Dòng thứ 3 của đoạn 2 (vì nó tối nên không thể nhìn thấy gì)