Giải bài tập:
1/ Chiều dài của 1 phân tử ADN là 0,408 micromet và có số Nu loại G bằng 35% :
a) Tính tổng số Nu và số vòng xoắn, khối lượng của phân tử ADN trên.
b) Xác định số lượng và tỉ lệ từng loại Nu của phân tử ADN trên.
2/ Một gen có 1950 liên kết hiđrô, có G= 450 và chiếm tỉ lệ 30% Tổng số Nu
a) Tính chiều dài phân tử ADN micromet?
b) Số Nu mỗi loại của phân tử ADN là bao nhiêu?
c) Tính số chu kỳ xoắn của phân tử ADN trên.
Chuyển đổi câu :
1. People have used the Internet all over the world
The internet has.....................
2. I think it would be a good idea to take the train
I suggest....................................
3. She went out, but she didn't say a world
She went out without...............
4. It is interesting to go out with friends at weekends
........................................................
5. What about going to the cinema tonight?
Shall we....................................
6. "Why don't you go with me ?" he asked me
........................................................
7. Does he spend most of his free time playing video games?
Does it take...............................
8. Does it take you 3 hours to do this task?
Do you spend............................
Put the verbs in brackets into the correct form :
1. Would you mind (open)...........the door?
2. I hate ( tell).........lies
3. I hope (see) .........you again
4. Jack avoid ( look).......at me
5. The teacher advised (buy).........a dictionary
6. The teacher advised me (buy)........a dictionary
7. We went (fish)........yesterday
8. He promised ( not be)...........late
9. My sister loves (read).............Picture books
10. I've stopped (smoke)........
11. She wants ( be).........a teacher
12. Let's star ( get).........ready
13. His friend stopped (buy)........a newspaper
14. You ought (do)........morning exercises
15. Your hair needs ( cut) ........
Câu trần thuật:
1. He asked the girl " Will you be here tomorrow ?"
2. "I am very grateful to you for such as wonderful evening, Mai" Said Lan
3. John told me "Marry is looking for the job at the moment "
4. She said "I am thinking about my childhood days "
5. She said to me " Can you use a computer ?"
6. David asked me " Could you tell me what time is it "
7. The interviewer said to me "Why do you want this job"
8. Tam said to Lan "I must leave for here for HN tomorrow"
Điền đúng thì :
1. He (arrive)..............while I (write)............my letter to you
2. Children (play)...........football in the street. I can hear the extreme noise
3. My brother (use)............this computer for 5 years
4. ...........you (cook)..........when I phoned you last night?
No, I (cut) ............flowers
5. I ( follow)..............this course since the beginning of the school
6. The librarian (arrange)............books and newspapers because pupils don't put them in the correct order
7. We ( have)........five tests so far this week
8. How long......you (study).......english? - For 2 years
Câu trần thuật:
1. Marry said " I am going to buy a new house"
2. They said " We must go home."
3. The school boy said to me "Who is Liz ?"
4. Marry asked me "Do you like me ?"
5. The farmer said "It may rain today"
6. They said " We must paint the blackbroard next week "
7. I said to Mrs. Brown "How do your children go to school ?"
Chọn đáp án đúng
1. If you (had bought, have bought, bought, bye) this car, you would have to pay for it youself.
2. I can't stop. I'm ( on, in, with, for) a hurry.
3. Hurry up or you won't ( catch, reach, take, do) the last train
4. You are going to come to the party, ( aren't you, will you, won't you, do you)?
5. ( Spend, Pass, Make, Have) a good weekend .
6. Yoko's pastime (vacation, hobby, career, business) is collecting seashells.
7. He told me to rest for a while.
"(Resting, To rest, Rest, Do you rest) for a while" he said
8. I haven't seen Nga ( for a long time, since long, lastly in the last time ).
9. There ( is, has, are, were) some bread on the plate.
10. What makes you ( having thought, to think, think, thinking) so?
11. Paola was very pleased (from, with, to, of) the birthday present her father gave her
12. We won't go out ( when, if, unless, if not) it stops raining.
13. "I have got a cold". ( Oh dear!, I regret it!, Bless you!, My dear!)
14. She will come to England (the last, next, last, the other) year
15. I was tired, (if, and, so ,but) I took a rest
16. They make their living by ( catch, to catch, catching, caught) fish in the river.
17. Last night we came to the meeting late (because, althought, despite, and) the traffic was very heavy.
18. Mr. Robinson has stayed here ( in, since, for, on) yesterday
Câu gián tiếp:
1. "I see her today". He said
2. " I don't like this flim". John said to marry
3.Hoa said to david . " I can't go to the movie with you tomorrow."
4." Where do you live?" she asked.
5. " Can you speak French and English ?" she asked
6. We said to them. "Your shoes are very nice."
7. "We'll stay home." Ba and Liz said
8. "What's your favorite color?" she said to me