1. it took me whole evening to finish my work

2. no one in the club is better than jenet

3. its difficult to train dogs

4. that exercise is more difficult than this one

24. tasty 

25. asleep

c

1. 

2. 

=120 : 53

3. 

vì số chia hết cho 2 và 5 có hàng đon vị là 0

số chia hết cho 3 thì tổng các chữ số phải chia hết cho 3

ta có :

5 + 4 + 3 = 12 (vậy thì b = 0) vì 12 + 0 =12 chia hết cho 3

vậy a = 0 và b=0

4. hình tự vẽ nha

chu vi hình chữ nhật :

(3 + 4).2 = 14(cm)

diện tích hình chữ nhật :

3.4=12 (cm2)

5.

chiều dài mảnh vườn :

chu vi mảnh vườn :

37. the worker is clever enough to make fine things from wood

38. my father explained the subject more clearly than my brother does

39. i used to live on the farm with my grandpa ten years ago

40. he spends all his free time collecting stamps

1. community service is a great way to help others 

2. people volunteer because they want to improve their community

3. we encouraged people to donated books and clothes to street children 

4. what can we do to help the environment clean ?

5. have you ever done any volunteer work ?

6. joe spent most of his free time doing volunteer work at a local hospital

7. what does your brother do in his free time

8. he usually goes climbling mountain in the summer

462 dm = 46 m 2 dm

1372 cm = 13 m 72 cm

4037 m = 4 km 37 m

1. x³ - 2x² - 8x

= x (x² - 2x - 8)

= x (x² - 4x + 2x - 8)

= x [x(x - 4) + 2 (x - 4)]

= x (x - 4) (x + 2)

2. 3x² - 6x

= 3x (x - 2)

3. x² - 2x + 1 - y²

= (x + 1)² - y²

= (x + 1 + y) (x + 1 - y)

4. 9x³ - 9x² - 4x + 4y

= 9x² (x - y) - 4 (x - y)

= (x - y) (9x² - 4)

= (x - y) (3x - 2) (3x + 2)

a

1. d

2. a

3. b

4. d

5. a

6. b

7. a

8. c

9. a

10. c