Tính giá trị biểu thức
D= $\frac{1}{1\times 4}+\frac{1}{4\times 7}+\frac{1}{7\times 10}+...+\frac{1}{97\times 100}$

Complete the second sentence in such a way that it means the same as the given one.

1.They weren’t listening carefully so they didn’t understand what she was saying.

      Ä They might _____________________________________________________________

2.You took me to your friend’s party and I met Hung.

      Ä If you __________________________________________________________________

3.If you don’t wear helmet, you can't ride your bike.

      Ä Unless __________________________________________________________________

4.I would visit my grandpa, but it’s raining.

      Ä If ______________________________________________________________________

5.It's a pity that I don't have enough money, so I can't buy that dress.

      Ä If ______________________________________________________________________

6.Sue didn't miss the train because I woke her up in time.

      Ä If ______________________________________________________________________

7.Dan got so angry because we were an hour late.

      Ä Dan wouldn't ____________________________________________________________

8.Julia didn't take her umbrella yesterday, so she got wet.

      Ä If Julia __________________________________________________________________

9.Study hard or you’ll fail the exam.

      Ä If ______________________________________________________________________

10.I don’t see you very often because you live so far.

      Ä If ______________________________________________________________________

11.I don’t have enough money, so I’m not going to buy that skirt.

      Ä I’d _____________________________________________________________________

12.We don’t practice English very often. We can't communicate with foreigners.

      Ä We could _______________________________________________________________

13.I can't meet you now. I have to work.

      Ä If ______________________________________________________________________

14.The weather was bad so we didn’t go camping yesterday.

      Ä If the weather ____________________________________________________________

15.You didn’t phone us so we didn’t get there in time.

      Ä We would ______________________________________________________________

16.I wasn’t able to help you because you didn’t explain the problem to me.

      Ä I might _________________________________________________________________

17.He didn't go to a university because he didn't pass the exam.

      Ä Had ____________________________________________________________________

18.I wouldn't have succeeded if my parents hadn't encouraged and supported me.

      Ä I wouldn't have succeeded but ____________________________________________

19.If he didn't help me, my children wouldn't enter primary school.

      Ä Without ________________________________________________________________

20.Peter left his job yesterday because of his low salary.

            Ä If Peter's salary   

Put the verbs in brackets into the correct form.

1.If Sarah ______ had asked_______ her teacher, she’d have answered her questions.         (ask)

2.If you spoke louder, your classmates  _____ would understand________ you.      (understand)

3.David  _____ would arrive________ there on time if he left early.                   (arrive)

4.You  _____ would have had________ no trouble at school if you had done your homework. (have)

5.If we _____________ to the cinema earlier, we _____________ the start of the film. (get)/(not miss)

6.They _____________ the exam if they studied harder.                                      (pass)

7.If Nick ______had_______ a bike, he could go on a bicycle tour with us.      (have)

8.If you  _____ swim________ in this lake, you’ll shiver with cold.                    (swim)

9.The door will unlock if he  ______ press_______ the yellow button.              (press)

10.If you _____________ me, I_____________ you my pen.                                 (ask)/ (lend)

11.What _____________ if she _____________ that new laptop?                         (Lina/ do)/(not buy)

12.Tom _____________ his mother do the gardening if she tells him a story this evening. (help)

13.If it _____________ , I will stay at home.                                                            (rain)

14.If they had enough money, they _____________ a new house.                      (buy)

15.If I were you, I _____________ John to the party.                                              (invite)

16.If the weather  _____________ fine, the children can walk to school.            (be)      

17.If we meet at 8.30, we  _____ will have________ a plenty of time.                  (have)

18.Lisa would find the milk if she  _____ looked________ in the fridge.           (look)

19.If you _____________ me for the tickets, I _____________ you some.           (ask)/(get)

20.I _____________ this flat if I _____________ how expensive it was.               (not hire)/ (know)

tìm 3 số tự nhiên thỏa mãn : a (a + 1) + (a + 1) + (a + 2) + (a + 2) = 26 .

Tính : 6:2.(1+2)=

sắp xếp các các chữ sau để được câu đúng

1, and/is/cold/It/windy

-

2, Ha Noi/far/is/from/Hue

-

3, He/playing/is/football

-

a, 3,2x125+36x140x1,25+0,18x1250

b,13,3+3,2x133+670x1,33

mong mọi người giúp ạ em đang cần gấp

                                                                 BÀI NÀY RẤT DỄ Nha

bài 1 Thùng thứ nhất có 16 lít dầu,thùng thứ nhất có số lít dầu bằng 1/8 số dầu thùng thứ hai.Hỏi thùng thứ hai có bao nhiêu lít dầu?

bài 2 Có 234 kg gạo chia đều vào 9 túi. Hỏi mỗi túi có bao nhiêu kg gạo? ( đây là bài rút veef dơn vị nha)

bài 3 Chị An măn nay 16 tuổi,tuổi của bố chị An gấp 3 lần tuổi của chị An.Hỏi hai bố con chị An năm nay bao nhiêu tuổi?