Bài 1

- Giả sử mạch 1 của gen là mạch gốc.

\(\rightarrow\%A_{mARN}=\%T_1=10\%\)

\(\rightarrow\%U_{mARN}=\%A_1=20\%\)

\(\Rightarrow\%A=\%T=\%T_1+\%A_1=30\%\)

\(\Rightarrow\%G=\%X=50\%-30\%=20\%\)

Bài 2

\(N=90.20=1800\left(nu\right)\)

\(\rightarrow rN_{td}=5.\dfrac{N}{2}=4500\left(nu\right)\)

Bài 3

- Giả sử mạch 1 của gen là mạch gốc.

\(\%A_1\ne\%U_{mARN}\) (loại)

- Giả sử mạch 2 của gen là mạch gốc.

\(\%U_{mARN}=\%A_2=25\%\)

\(\%G_1=\%X_2=\%G_{mARN}=30\%\)

\(\%A_1=\%T_2=\%A_{mARN}=15\%\)

\(\%G_2=100\%-\%T_2-\%A_2-\%X_2=30\%\) \(=\%X_{mARN}\)

1. I have played soccer since i was six years old.

=> I started playing soccer when I was six years old.

2. We have been good friends for a long time.

=> We started being good friends a long time ago.

3. They have trained the parrots since last year.

=> They began training the parrots last year.

Give the correct of verbs in brackets:

31.I imagined (win) ...winning...the first prize in the speaking competition

32.I haven't studied for ages and I'm finding it hard to get used to (study).........studying...... every day

 33.I feel that learning English will help (improve)......to improve......my chances of promotion at work.

34. John used to (travel).......travel............... a lot in his job but now,since his promotion, he doesn't.

35.European drivers find it difficult to get used to (drive)........driving..........on the left when they visit Britain.

36.My father refused (lend).....to lend.....his car because of her carelessness

37. The boys admitted (not/collect)...not to collecting.....litter this morning.

38. The girl regrets (not/guide)...not guiding....her friends more carefully.

39.It's no good (read)..reading..this novel.

40.My mother gave me a dictionary in order for me (learn) ....to learn.english better

Give the correct of verbs in brackets:

21. They would win the contest if they (practise)...practised...more last week.

22.The coach (leave)....will leave.......the stadium by the time some journalists come.

23. The girls denied (punish)..punishing..due to their being late.

24.My father advised me (go) ...to go....swimming in the early morning.

25.This film deserves (win).to win...the first prize in on the telefilm festival.

26.We hope (win) ..to win...the first prize in the competition last week.

27.It's no good (give) ...giving....him this smart phone because he doesn't know to use it.

28.The boss appreciated (have)...having....a good opportunity to invest in this company.

29. Our team have planned (start)..to start... a new project in spring.

30. Everyone thinks that (listen)...listening.....to pop the first prize in the speaking competition.

Give the correct of verbs in brackets:

11. I would like you (eat)...to eat..out with us tonight.

12. My mother often has her friends (show)..show...how to cook a healthy meal

13. We were worried about (hand)...handing. in our assignment last week.

14. Since last summer, I (not/keep)...haven't kept..contact with some schoolmates.

15. My child (give)..is given...a nice present on his birthday every year.

16.The woman warned us against (swim)..swimming...in this river

17. She failed (get)..to get..through to her old friends

18. Nam was the first student (know).to know...the details of their plan.

19. The police threatened (arrest)..to arrest..the boy if he didn't return the key. 

20. The girl refused (give)...to give.....him her address.

Give the correct of verbs in brackets:

1. My parents are considering (buy)....to buy.....a new house in the centre of this city.

2. Mary decided (not/ put).not to put...the meeting.

3.The boys had no difficulty in (persuade) ...persuading...the man to let them (play) ..play.... in his garden

4. The boss often makes his employees (work)...work..overtime at the weekend. the pollution.

5. She suggested (not/hold)..not holding....the discussion about the pollution

6.The teacher ordered us (stop)....to stop..(write)...to write.......when the bell rang

7.It's silly of him (spend)...to spend...a lot of money (buy)..buying....a second hand bike

8. My mother will help me some housework if she (have)....has..much free time

9. After they have completed this project, they (move)..will move...to another city

10. We should avoid (travel)...travelling...in the rush - hour traffic.

Ex1: Circle the correct form of the verbs. - Gạch chân / khoanh tròn đáp án đúng (chép cả câu vào vở ghi)

1. If you take / will take vitamin C, you won’t get a cold.

2. If the kids play baseball there, they break / will break the window!

3. I’ll call you tomorrow if I hear / will hear any news.

4. If you stay / will stay at that hotel, it’ll be very expensive.

5. Jack is / will be sad if he doesn’t see you tomorrow.

6. If you see / will see an accident, call the police!

7. You be / ‘ll be cold if you go out without a coat.

8. If you go to bed early tonight, you feel / will feel better in the morning.

9. If I miss / I’ll miss lunch, I’ll get a sandwich later.

10. We’ll have to leave without John if he doesn’t arrive / he won’t arrive soon.

11. Will you send me a text when you reach / you’ll reach Mexico City?

12. If I make some coffee, do you cut / will you cut the cake?

Ex2: Rewrite the following sentences. (Viết lại câu giữ nguyên ý nghĩa, sử dụng câu điều kiên loại 1)

1. Unless he takes these pills, he won’t get better.

→If he doesn't take these pills, he won't get better.

CONDITIONAL SENTENCES: CÂU ĐIỀU KIỆN LOẠI 1 REVISION -2023 2

2. Study harder or you won’t pass the exam.

→If you study harder, you will pass the exam.

3. Save water or you’ll have to pay an enormous bill.

→If you don't save water, you will have to pay an enormous bill.

4. It may rain this afternoon, so they’ll probably cancel (hủy bỏ) the match.

→If it rains this afternoon, they will probably cancel the match.

6. The children don't need to have all of these books to start the course.

7. We need them completed to report on Friday.

8. My mother wants me to stay at home after 9.00 pm.

9. My parents always encourage me to work hard at school.

10. The increase in oil price will certainly affect other fields.

\(a,N=\dfrac{2L}{3,4}=2000\left(nu\right)\)

\(b,\) \(\dfrac{N}{20}=100\left(ck\right)\)

\(c,\) Ta có: \(A=T=30\%N=600\left(nu\right)\)

\(\rightarrow X=T=20\%N=400\left(nu\right)\)

\(d,H=2A+3G=2400\left(lk\right)\)