Giúp mình từ câu 26 đi vs ạ

26, Protecting the environment is important.

27, He studies hard in order to get a scholarship.

28, It took me two hours to do this exercise.

29, Lan said that she could play the piano very well.

30, I spent two hours doing this homework.

31, If you don’t water these trees, they will die.

32, It’s the first time I have ever seen this style of jeans.

33, The books must be returned by this Friday.

34, Mark has played the piano for ten years.

35, It’s the first time I have ever seen this style of jeans.

36, I wish I had my teacher’s address.

37, The weather was bad, so we didn’t go on a picnic.

38, That house was built three years ago.

39, Hoa asked me if I liked pop music.

40, Why don’t we plant some trees around our house to get more fresh air?