34. This is the first time Jack has visited Hoi An ancient town.

35. If we work hard, we'll make this beach clean and beautiful again.

36. A show was organized to raise money for charity yesterday by the students

has made/joined

Cho hệ phương trình {x+(m+1)y=14x−y=−2x+m+1y=14x−y=−2. Tìm m để hệ phương trình có nghiệm (x; y) thỏa mãn