có ai biết làm bài này không giúp mình với mình đang cần rất rất là gấp mong các bạn giúp cho , xin cảm ơn
II. Choose the best answer
1.I come from Canada. Where .................you..................from?
a. do.............come b. did ...... come c. are ..........coming d, have .....come
2. The telephones…………..by Alexander Graham Bell
A. is invented B. is inventing C. Invented D. was invented
3. The swimming pool .............. at 9 o’clock and ............ at 18.30 everyday.
a. opens............. closes b. opens ...... closed c. opened...... closed d. opened......... closes
4. Three swimmers, Paul, Ed, and Jim, ................ now in competition for medals.
a. is b. has been c. had been d. are
5. Listen ! I .............. somebody knocking at the front door.
a. am hearing b. heard c. have heard d. hear
6.. ………………………………………..yet?
A. Have the letters been typed B. Have been the letters typed
C. Have the letters typed D. Had the letters typed
7. At 5 o’clock yesterday evening, I ……………my clothes.
a. am ironing b. have ironed c. ironed d. was ironing.
8. I ………………..along the street when I suddenly heard footsteps behind me.
a. was walking b. am walking c. walk d. walked.
9. She ………….German for two years.
a. has learnt b. is learning c. learn d. learns.
10. When I last………..Jane, she ………..to find a job.
a. see/was trying b. saw/was trying c. have seen/tried d. saw/tried.
12. French is a…………language to learn than English is.
A. difficult B. more difficult C. most difficult D. more and more difficult
13. The more polluted air we breathe,…….we get.
A. the more weaker B. the more weak
C. the weaker D. weaker more
14. The more we study, the……we are.
A. more good B. better C. better than D. good
15. The more I tried my best to help her, ……….she became.
A. less lazy B. the lazier C. the more lazy D. lazier
16. The weather becomes………………
A. colder with colder B. colder and colder
C. colder and more colder D. more and more cold
17. The more he slept,…………….irritable he became.
A. the most B. the vey more C. much more D. the more
18. ………..he worked, the more he earned.
A. The more hard B. The hard C. The harder D. The hardest
19. ………I get to know Jim, the more I like him.
A. For more B. More C. The more D. The most
20. The competition makes the price of goods……….
A. most cheap and cheap B. cheaper and cheaper
C. more cheap and more cheap D. cheaper and more cheaper
III. Rewrite:
1) Although Tom was a poor student, he studied very well.
=> In spite of ………………………………………………………
2) Mary could not go to school because she was sick.
Because of ………………………………………………………………..
3) Although the weather was bad, she went to school on time.
=> Despite ……………………………………………………………..
4) My mother told me to go to school although my stomachache was sick.
=> In spite of ………………………………………………………………..
5) Because there was a big storm, I stayed at home.
=> Because of ……………………………………………………..
6) Tom was admitted to the university although his grades were bad.
Despite …………………………………………………………………………
7) Although she has a physical handicap, she has become a successful woman.
=> Despite ……………………………………………………………………….
8) In spite of his good salary, Tom gave up his job.
=> Although………………………………………………………..
Theo TCDTSBN có:
\(\frac{a}{3}=\frac{3}{b}=\frac{b}{a}=\frac{a+3+b}{3+b+a}=1\) (vì a+b khác -3)
=> a/3 = 1 => a = 3 (1)
3/b = 1 => b = 3 (2)
b/a = 1 => b = a (3)
Từ (1),(2),(3) => a=b
Áp dụng tính chất dãy tỉ số bằng nhau ta có :
\(\frac{a}{3}=\frac{3}{b}=\frac{b}{a}=\frac{a+3+b}{3+b+a}=1\)
\(\hept{\begin{cases}\frac{a}{3}=1\Rightarrow a=3\left(1\right)\\\frac{3}{b}=1\Rightarrow b=3\left(2\right)\end{cases}}\)
Từ (1) và (2) \(\Rightarrow\frac{a}{b}=\frac{3}{3}=1\) <=> a=b (đpcm)