don't thrown trash__________the water?

A.onto         B.in         C.into          D.on

why don't you use public buses instead______motorbikes ?

a.of       B.in         C.off           D.on

1. Coal , oil , gas.......are 

A. Nature         B.Natural             C.Naturally        D.Unnaturally 

2.she has____________provided a pinic lunch for us

A.kind             B.kindnees            C.kindly             D.unkind

3.We'll make this beach clean and____________again 

A.Beautiful      B.beauty               C.Beautifully      D.Beautify

4.in Many countries, people crowd the street to watch_____________parades

A.color            B.colorfully            C.colorful          D.Colorless

5.the chiledren laughed_____________when they played with their toys

A.happy          B.unhappy            C.happily          D.happiness

6.I can speak english_________________

A.good            B.well                   C.Bad                 D.Quick

7.this test must be do ne __________________

A.care            B.careful            C.carefully          D.Careless

8.lan's voice is soft . she speaks very__________________

A.loud            B.loudly            C.soft                  D.softly

9.what will they achieve if the work______________today 

A.hardly            B.hard            C.harden          D.hardness

10.the soccer players have played________________

 A.beauty            B.baeutiful            C.beautify          D.baeutifully

21/ The train couldn’t run ______ snow.

A. because                         B. because of              C. since                       D. though

22/ Paul isn’t going to the concert _______ the tickets are too expensive.

A. because                         B. because of              C. so                            D. and

23/ It was raining .  ________, the soccer match was going on.

A. And                              B. However                 C. Therefore                D. But

24/ _____ it was so cold, he went out without an overcoat.

A. If                                  B. Since                       C. Although                D. So

25/ It hasn’t rained for ages. _______, the ground is very dry.

A. And                              B. But                         C. Therefore                D. So

26/ Lan doesn’t like sports. ______, she doesn’t mind watching football matches.

A. But                               B. And                                    C. So                           D. However

27/ He didn’t have much money, _____ he bought a lot of things at the shop for Tet.

A. but                                B. and                         C. however                  D. although

6/ _________they live near us, we can see them very often.

A. Even                       B. So                           C. But                         D. Since

7 / Tom failed the exam ______________his laziness.

A. because of              B. because                   C. in spite of               D. though

8 /  The barbecue was cancelled ___________the heavy rain.

A. because                   B. because of              C. although                 D. in spite of

9/ ______________the forest is important to the environment, people should stop cutting down trees.

A. Despite                   B. Though                   C. Since                       D. Because of

10/ __________there are many celebrations throughout the year, Tet is the most important celebration for Vietnamese people .

A. Because                  B. But                                     C. Although                D. As

11/ __________it rained, the boys played football.

A. Even                       B. Even though           C. Despite                   D. In spite of

12/ __________I heard the telephone ring, I didn’t answer .

A. Because                  B. Only if                    C. Even though           D. So  

13/ She didn’t apologize___________ she was an hour late.

A. in spite of               B. even though            C. however                  D. because

14/ _____________it was late , I decided to phone Brian.

A. Despite                   B. In spite of               C. However                 D. Though

15/ He went out without an overcoat_________ it was so cold.

A. if                                         B. although                 C. because                   D. since

16/ Mr. Pitt still lives in a small flat__________ having a lot of money.

A. although                 B. even though            C. in spite                    D. despite

17/ Some English words have the same pronunciation_______________ they are spelled differently, for example, deer and dear.

A. though                    B. unless                      C. since                       D. only if

18/ I’d love to go to the party ______ I have to finish my homework.

             A. but                         B. because                   C. therefore                 D. however

19/ He bought a lot of things: notebooks, pens ____ pencils from the shop.

A. but                                B. or                            C. and                         D. so

20/ Would you like tea _____ coffee ?

A. and                               B. but                          C.so                            D. or

 giúp tui mấy bài này đi mọi người

giải hệ Phương trình 

1. \(\left\{{}\begin{matrix}1,3x+4,2y=12\\0,5x+2,5y=5,5\end{matrix}\right.\)

3. \(\left\{{}\begin{matrix}0,35x+4y=-2,6\\0,75x-6y=9\end{matrix}\right.\)

4. \(\left\{{}\begin{matrix}2x-y=5\\-x+y=-2\end{matrix}\right.\)

7. \(\left\{{}\begin{matrix}19x-21y=15\\16x-21y=6\end{matrix}\right.\)

8.\(\left\{{}\begin{matrix}4x-3y=4\\-6x+7y=4\end{matrix}\right.\)

9.\(\left\{{}\begin{matrix}-7x+4y=-1\\5x-4y=-5\end{matrix}\right.\)

11.\(\left\{{}\begin{matrix}8x+5y=20\\1,6x+2y=0\end{matrix}\right.\)

12. \(\left\{{}\begin{matrix}4x+3y=5\\2x-5y=9\end{matrix}\right.\)

14. \(\left\{{}\begin{matrix}-3x+8y=72\\7x+9y=-2\end{matrix}\right.\)

15. \(\left\{{}\begin{matrix}\dfrac{x}{2}+2y=\dfrac{7}{2}\\2x-y=\dfrac{19}{2}\end{matrix}\right.\)

giả các hệ phương trình sau bằng phương pháp thế 

a{ 3x-y=5 , 5x+2y=23  

b{ 3x+5y=1 , 2x-y=-8 

c{ \(\dfrac{x}{y}=\dfrac{2}{3}\) , x+y-10=0

2 . nhận biết các dd ko màu ao bằng phương phap hoa học : HCl, H₂SO₄ , NaOH , K₂SO₄

1. thực hiện các chuỗi hoa học ai ( ghi rõ điều kiện nếu có )

a) Cu -> SO₂ -> SO₃ -> H₂SO₄ -> HCl

b) HCl -> SO₂ ->SO₃ -> Na₂SO₄ ->NaCl

c) Cu -> SO₂ -> SO₃ -> H₂SO₄ -> HNO₃

d) Cu -> CuSO₄ ->CuCl₂

e) Cu -> CuO -> Cu(NO₃)₂

f) CuCl₂ -> Cu(NO₃)₂ -> Cu(OH)₂ -> CuSO₄ -> CuCl₂

5.

cho \(\Delta ABC,\)góc A=90 , AB=5 , BC=7 . giải tam giác vuông ABC ( kết quả về góc làm tròn đến phút , cạnh đến chữ số thập phân thứ 3)