-> We suggest cooking food for the elderly people.

Bài 2:

a, Xét tam giác ABC và tam giác CDA có:
AB = CD
AC chung
AD = BC
⇒ ΔABC = ΔCDA (c-c-c) (dpcm)
b, Do ΔABC = ΔCDA  ⇒ \(\widehat{BCA}=\widehat{DAC},\widehat{BAC}=\widehat{DCA}\) (cặp góc tương ứng)
mà: \(\widehat{BCA},\widehat{DAC}\) là 2 góc ở vị trí so le trong ⇒ BC//AD (dpcm)
       \(\widehat{BAC},\widehat{DCA}\) là 2 góc ở vị trí so le trong ⇒ AB // CD (dpcm)

Bài 1:

a, H là trung điểm của BC ⇒ BH = CH
Xét tam giác ABH và tam giác ACH có:
AB = AC
AH chung
BH = CH
⇒ ΔABH = Δ ACH (c-c-c) (dpcm)
b, Do ΔABH = Δ ACH ⇒ \(\widehat{AHB}=\widehat{AHC}\) (2 góc tương ứng)
mà \(\widehat{AHB}+\widehat{AHC}=180^o\) (do 2 góc kề bù)
\(\Rightarrow\widehat{AHB}+\widehat{AHB}=180^o\)
\(\Rightarrow2\widehat{AHB}=180^o\)
\(\Rightarrow\widehat{AHB}=180^o:2=90^o\) \(\Rightarrow AH\perp HB\) hay \(AH\perp BC\left(dpcm\right)\)

b xem lại đề bài nhé, ở chỗ vận tốc xem có bị sai đơn vị ko

VII
1. They have built this house for 2 months.
2. My father hasn't met me since last week.
3. Lan has never written to Maryam before.
4. The last time I met her was 3 years ago.
5. It's four years since we began learning English.

VI
1. studied
2. have studied
3. have never watched
4. watched
5. have traveled
6. traveled
7. have read
8. read
9. had
10. have had
11. have had
12. have lived
13. went
14. stayed
15. haven't seen / hasn't visited
16. has been
17. has worked
18. moved/ I have been
19. wore
20. have been
21. met
22. has become
23/ have felt / lived
24. was/ haven't seen 

D
Giaithich: \(\overrightarrow{CB}+\overrightarrow{AC}=\overrightarrow{AC}+\overrightarrow{CB}=\overrightarrow{AB}\)

V
1. called
2. met
3. have flown / went
4. did (your father) give up
5. moved
6. have been
7. spent
8. have watched
9. delivered
10. heard
11. have had/ gave

I READING
A/
1.Charlotte
2.18
3.They are teachers.
4.They want their children to understand that work comes before the play
5.She felt bad.
B/
1.C
2.B
3.C
4.D
5.A

II LANGUAGE
A.
1/A
2/B
3/C
4/D
5/C
6/D
B.
1/doing
2/tidy
3/detector
4/entertaining
5/complaint
6/quality