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Tìm GTLN,GTNN của hàm số y=1/2.sinxcosx -cos^2 x +1.

XIV. Make sentences using the cues given 1. last year/we/ start/ community garden/ project. => ………………………………………………………………………………………………. 2. so far/ we/ ask/ people/ donate/ books and clothes/ the poor children. => ………………………………………………………………………………………………. 3. because/ the lake/ be/ full/ rubbish/ they/ decide/ clean it up/ last Sunday. => ……………………………………………………………………………………………….. 4. Green Summer/ organize/ first time/ in 1997. => ……………………………………………………………………………………………….. 5. Go Green/ non- profit/ organization/ that / protect/ environment. => ………………………………………………………………………………………………. 6. When/you/ start/ work/ this charitable organization? => ………………………………………………………………………………………………...

VIII. Arrange the words to make sentences. 1. way/ others/ community/ a/ help/ service/ is/ great/ to/. ……………………………………………………………………………………… 2. they/ community/ people/ because/ volunteer/ want/ improve/ to/ their/. ………………………………………………………………………………………. 3. encouraged/ books/ people/ street children/ we / to/ donate/ and clothes/ to ……………………………………………………………………………………………. 4. what/ to / help/ we/ can/ do / the /environment/ clean/? …………………………………………………………………………………………….. 5. work/ done/ you/ ever/ have/ volunteer/ any? …………………………………………………………………………………………… 6. free time/Joe/ doing / work/ spent/ most/ at/ his/ local hospital/ a / of / volunteer. …………………………………………………………………………………………… IX. Write the second sentences so that it has the same meaning as the first one. Use the word in brackets 1.I’m leaving now because I don’t want to miss the train. (so) => I’m …………………………………………………………………………………….. 2. The last time I saw my uncle was two years ago. (for) => I haven’t ……………………………………………………………………………….. 3. Let me reach my office and then I will talk to him. (when) => …………………………………………………………………………………………. 4. Why don’t we donate our old books, toys and clothes to charity? (suggests) => Mom ………………………………………………………………………………….. 5. Jane stayed behind after the class in oreder to talk to the teacher. (because) => Jane …………………………………………………………………………………… 6. This is the first time they’ve been to Korea. (before) => They’ve ………………………………………………………………………………. 7. How long have you been a member of Volunteers In Asia? (join) => When …………………………………………………………………………………. 8. We suggested people recycle glass, cans and papers. (encouraged) => We ……………………………………………………………………………………… X. Write the correct form or tense of the verbs in brackets. 1.Jasmine ___________ (fail) her driver’s test three times! 2. They _______ (establish) the Viet Nam Red Cross Society in 1946. 3. How long _______ (they/ live) here? – They _________ (move) here two years ago. 4. So far, we ___________ (finish) half of our work. 5. I’m really busy now. I _____________ (study) for the final exam. 6. When _____________ (you/ buy) these shirts?- I ____________(buy) them yesterday. 7. __________________ (you/ ever/be) to Japan? – No, I __________(not be) to Japan yet. 8. Claire ______________( volunteer) at the homeless shelter once a week. 9. We volunteer _____________( help) the elderly in a nursing home. 10. Jane suggested _____________ (donate) old books, and toys to needy children XI. Supply the correct form of the words in brackets 1. Community ________________ have a lot of positive effects on students.(serve) 2. ______________ people find it difficult to have a job. (disable) 3. I’d like to work as a volunteer for a charity ___________(organise) 4. He made a $ 5000 ___________ to charity. (donate) 5. The Soup Kitchen is a ____________ organisation that prodives free meals for needy people. (profit) 6. The homeless shelters are entirely staffed by _______________ workers. (volunteer) 7. The organization is funded by _____________ donations. (charity) 8.We help the _______________ with housework and garderning. (old) XII. These is one mistake in each sentence. Underlined and correct the mistake 1.She has went to visit Susan. She’ll be back tomorrow. 2. I didn’t done any volunteer work lately. 3. Matha is a great cooker and she often cooks dinner for homeless people. 4.Kim hasn’t seen the film already, so don’t tell her how it ends. 5. She has doneted a lot of money for local charities. 6. Before donate a book, make sure that it is in good condition. 7. We should encourage people recycle glass, cans, plastic and paper. 8. Did you lived in Vancouver when you were young? XIII. Choose the word which best fits each gap. Doing some form of voluntary work has (1) …………… been more popular with British people. Over 20 million people were engaged (2) ……………. voluntary activities in 2013. Vounteering means giving up time to do work of (3) ……………. to the community. It can be based in the UK or overseas. Volunteering can take many forms, from working with children with (4) …………… difficulties, in an animal hospital, or planting trees. (5) ……………. London won its bid to host the 2012 Olympics, up to 70,000 (6) ……………… were needed to help ensure the games were a success. 1a. ever b. any c. never d. before 2. a. with b. in c. to d. for 3. a. comfort b. benefit c. contribute d. profit 4. a. learn b. learned c. learning d. learnt 5. a. When b. While c.Where d. What 6. a. donors b. visitors c. foreigners d. volunteers

The litter là số ít hay số nhiều?

Đốt cháy hoàn toàn một este no, đơn chức A cần 78,4 lít không khí (đktc) thu được 10,8 g H2O. CTPT của este này là : A. C3H6O2 B. C4H8O2 C. C2H4O2 D. C5H10O2

3^x - 1 + 5 . 3^x - 1 (2x - 1) ^6 = (2x -1)^8

một trường tiểu học gái ít hơn trai 120 hs biết gái = 3/7 trai tính số hs trai vs gái

$\frac{2}{3}$ - x + $\frac{3}{4}$ = 3

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