4. Complete the sentences:
1 Can you explain the reason?
2 Did Dad cook dinner yesterday?
3 Did the pupils ask any questions?
4 Did the girls enjoy the party?
5 Did you visit the museum last weekend?
6 Did Charles arrive early last night?
7 Did Mr. Green water the plants?
8 Did your sister type the letter?
9 Did you have a picnic on a farm yesterday?
5. Give the correct form of the verbs (negative form):
1 David did not watch the film in the cinema.
2 Carol did not appear for the party.
3 My parents did not book a table in the restaurant.
4 Peter did not close the door when he entered.
5 I did not wait for you because I was in a hurry.
6 I did not go to the office last Monday.
7 She did not join the English club last weekend.
8 Mary did not understand the last lesson.
9 We did not have English yesterday.
10 My friends were not at school.
11 She did not buy a new ruler yesterday.
12 He did not talk with his parents about his vacation in Da Lat last year.
13 They did not come to school yesterday.
14 The windows were not closed yesterday.
15 We did not return home at 7 pm last Monday.
16 She did not eat fish and crab yesterday.
6. Change these sentences into the negative form:
1 She did not have a nice dress yesterday.
2 I did not come to school late.
3 Our class did not win in the football competition.
4 Jane did not go to London last week.
5 He did not see Kate on TV last night.
6 Bob did not look so happy yesterday.
7 The man did not drink a lot of wine in the past.
8 The cook did not prepare some pasta.
9 The children did not sing songs at the party last night.
10 We were not on the beach last summer holiday.
7. Reorder the words to make the correct sentences in “question” form:
1 Did you do homework yesterday?
2 Did he see an interesting film on Sunday?
3 Did Jim go to the sports club last week?
4 Did Lucy send a message to her friend?
5 Did Tom get a new task yesterday?
6 Did they meet their guests at the bus station?
7 Did Nick ride his bike to school yesterday?
8 Did you go to the hospital last week?
9 Did your children sing at the party?
10 Did she wear a new dress at the party last night?
8. Read and underline the correct phrase:
1 George didn't want to be a doctor.
2 Did you help your mother?
3 We did not understand you.
4 Did he paint the fences?
5 I didn't finish my homework.
6 Did she call me?
7 The gardener didn't water the flowers.
8 Did the students solve the questions?
9 Emma did not go shopping.
10 Did you wear a coat?
11 Mina didn't miss the bus.
12 Did your aunt visit you?
13 My brother did not watch TV.
14 I didn't answer all the questions.

46 United Nations Volunteers (UNV) is a UN organization that supports sustainable human development globally through the promotion of volunteerism, including the mobilization of volunteers.
47 It serves the cause of peace and development through enhancing opportunities for the participation of all peoples
48 Volunteering brings benefits to the individual volunteer as well as to society, enhances social cohesion, and enriches communities
49 In this context, UNV volunteers take part in various forms of volunteerism and play a role in development and peace together with co-workers, host agencies, and local communities
50 Engaging in volunteer activity can effectively and positively enrich your understanding of local and social realities, as well as create a bridge between yourself and the people of the host community

Lucy Grand sent us a play (51) about the life of English children, and we (52) decided to give a performance at our club. We invited some (53) actors from the children's (54) theatre to help us. They (55) explained everything to us. Now everybody has his or her (56) part in the play and must learn it (57) by heart. Ann is a good (58) dancer and she will dance. Nelly will sing. The girls have (59) made a beautiful dress for her. Our (60) form teacher says that if the play is good, they will show it on television.

What time were you at home yesterday

1 Watch out! The tree falls down behind you
2 Jane and her children are playing happily in the garden
3 Why do you always get up late in the morning
4 Why do they always make the room dirty
5 What is Rosa doing during the vacation
6 I need to boil some eggs

15 I have black hair. Alice's hair is also black.
-> Alice's hair is the same color as mine.

16 The station was nearer than I thought.
-> The station was not as far as I thought.

17 Our neighbours have lived here for quite a long time, but we have lived here longer.
-> Our neighbours haven't lived here as long as we have.

18 My mother's favourite food is noodles. My favourite food is bread.
-> My mother likes noodles, but I like bread.

19 The number of students in this class is 40. That class also has 40 students.
-> This class has the same number of students as that class.

20 My favourite subject is English. My sister is also interested in Math.
-> I like English, and my sister likes Math.

\(k.5x-3x=20\\ x\cdot\left(5-3\right)=20\\ x\cdot2=20\\ x=10\)

\(h.12x+13x=2000\\ x\cdot\left(12+13\right)=2000\\ x\cdot25=2000\\ x=80\\ i.\left(x-4\right)\cdot\left(x-3\right)=0\\ \Rightarrow x-4=0\Rightarrow x=4\\ x-3=0\Rightarrow x=3\\ \text{ vậy x = 4 hoặc x = 3 thì }\left(x-4\right)\cdot\left(x-3\right)=0\\ \)

\(a.5\cdot\left(12-x\right)-20=30\\ 60-5x-20=30\\ 5x=10\\ x=2\\ b.\left(50-6x\right)\cdot18=8\cdot9\cdot5\\ 900-108x=360\\ 180x=540\\ x=3\\ c.128-3\cdot\left(x+4\right)=23\\ 128-3x-12=23\\ 3x=93\\ x=31\\ d.\left[\left(4x+28\right):3+55\right]:5=35\\ \left(4x+28\right):3=120\\ 4x+28=360\\ 4x=332\\ x=83\\ e.6x+4x=2010\\ x\cdot\left(6+4\right)=2010\\ 10x=2010\\ x=201\\ f.200-\left(2x+6\right)=64\\ 2x+6=136\\ 2x=130\\ x=65\)

\(g.135-5\cdot\left(x+4\right)=35\\ 5\cdot\left(x+4\right)=100\\x+4=20\\x=16\)

\(\dfrac{2}{3}+\dfrac{-1}{-4}+\dfrac{1}{21}+\dfrac{1}{12}\\ =\dfrac{8}{12}+\dfrac{3}{12}+\dfrac{1}{12}+\dfrac{1}{21}\\ =\dfrac{12}{12}+\dfrac{1}{21}=1+\dfrac{1}{21}=\dfrac{22}{21}\)