He never suspected that she was a witch.

A.  Never has he suspect she was a witch.

B.  He used to think she was not a witch,

C.  At no time did he suspect that she was a witch.

    I should have studied last night but I was too tired.

A.  I studied last night because I had to.

B.  I tried to study last night but the material was too hard.

C.  I couldn't study last night because I was very tired.

  Only after she had gone home                  .

A.  she realized that she had left the bag on the train.

B.  did she realize that she left the bag on the train.

C.   did she realized that she had left the bag on the train.

D.  did she realize that she had left the bag on the train.

         owned expensive cars as today.

A.  Never had so many young people

B.  Never so many young people

C.  The young people aren't ever

D.  The young people who have never

  I have gained much experience since                 .

A.  I worked here with you.

B.  I have been working here with you.

C.  I have worked here with you.

   Hung's score on the English test is the highest in the class               .

A.  He must have studied hard

B.  He should have studied hard

C.  He should study hard

  Hung's score on the English test is the highest in the class               .

A.  He must have studied hard

B.  He should have studied hard

C.  He should study hard

     Only in this way                 after leaving university.

A.  you will get a good job

B.  can you get a good job

C.  were you able to get a good job

   Because the first pair of shoes didn't fit her, she asked for           

A.  another shoes                      B. other pair

    I would prefer you not to smoke here.

A.  I'd rather you didn't smoke here.

B.  I'd rather you don't smoke here.

C.   I'd rather you shouldn't smoke here.

  They visited the museum and then they had lunch in a restaurant.

A.  After having lunch in a restaurant, they visited the museum.

B.  After they visited the museum, they had lunch in a restaurant.

C.  After they had visited the museum, then they had lunch in a restaurant.

  The train journey from Hanoi to Hai Phong lasted two hours.

A.  It is two- hour train journey from Hai Phong to Hanoi.

B.  It was a two- hours train journey from Hai Phong to Hanoi.

C.  It was a two- hour train journey from Hai Phong to Hanoi.

D.  It was a two hour train journey from Hai Phong to Hanoi.

   Daisy hasn't seen her sister since she left for America.

A.  The last time Daisy had seen her sister when she left for America.

B.  The last time Daisy saw her sister was when she left for America.

C.  Daisy last saw her sister on her departure for America.

  I regret doing business with that dishonest man.

A.  I wish I didn't do business with that dishonest man.

B.  I wish I hadn't done business with that dishonest man.

C.  I wish I had done business with that dishonest man.

 You can rely on Nam to give you any help you may need.

A.  Should you require any assistance, you can count on Nam for it.

B.  Let Nam know if you need any help with this.

C.  If you need help of any kind, be sure to let Nam know.

  The test we did yesterday was very long. It was very difficult, too.

A.  Not only was the test we did yesterday very long but also very difficult.

B.  Not only was very long the test we did yesterday but it was also very difficult.

C.  The test we did yesterday was not only very long but it was also very difficult.

D.  Not only the test we did yesterday was very long but also very difficult.

      She bought some candles this morning because the electricity may be cut off this evening.

A.  She bought some candles this morning in case the electricity might be cut off this evening.

B.  In the event that they will cut off the electricity this evening, she bought some candles this morning.

C.  In case the electricity is cut off this evening, she bought some candles this morning.

          not until 1915 that the cinema really became an industry.

    Greenhouse gases, like carbon dioxide, accumulate in the atmosphere and                     from escaping from the planet.

A.  to prevent the sun's heat               B. the sun's heat prevent

C. prevent the sun's heat                   D. the sun's heat prevents

  It costs me a fortune, but I don't regret                a year travelling around the world.

A.  Spent               B. to spend           C. spending          D. have spent

         is caused by a virus was not known until 1911.

A.  That measles                                 B. measles

The type of plant and animal life living in and around a pond depends on the soil of the pond,                    and the pond's location.

A.  What the quality of the water is

B.  how is the water quality

C.  The quality of the water

                of economic cycles been helpful in predicting turning points in cycles, they would have been used more consistently.

A.  Psychological theories                  B. Psychological theories have

C. Had psychological theories          D. Psychological have theories

           a successful rock star, a singer must have stage presence and charisma in addition to mere musical talent.

A.  To become                                    B. Becomes

             the fifth largest among the night planets that make up our solar system.

A.  The Earth being                            B. The Earth is

  Marilyn Monroe's story is well-known: an unhappy childhood,       several marriages and divorces, and eventual suicide.

A.  a struggle to become a star

B.  she was struggling to become a star

C.  she became a star

D.  then a star she became

  Marilyn Monroe's story is well-known: an unhappy childhood,       several marriages and divorces, and eventual suicide.

A.  a struggle to become a star

B.  she was struggling to become a star

C.  she became a star

D.  then a star she became

 Florida,              the Sunshine State, attracts many tourists every year.

A.  is                                         B. known as

C. is known as                         D. that is known as

 Florida,              the Sunshine State, attracts many tourists every year.

A.  is                                         B. known as

This is              the most difficult job I have ever done.

   No matter how hard he tried, Nam could not make sense of his economics textbook

A.  If Nam had studied harder, he would have been able to comprehend what was in his economics textbook

B.  In spite of his efforts, Nam was unable to understand the contents of his economics textbook

C.  Nam could not understand his economics textbook because he hardly tried to at

D.  It was impossible for Nam to understand his economics textbook without making a great effort

 Four miles off the southeastern coast of Massachusetts              a popular summer resort.

A.  lies the island of Martha's Vineyad

B.  the island of Martha's lie there

C.  does lie the island of Martha's Vineyad

D.  where the island of Martha's lies

OA=2cm OB=5cm tính AM

  đốt nóng hợp chất hidro sunfua trong 1 bình kín không có không khí.Biết rằng chắc chắn có phản ứng hoá học xảy ra;
chất sản phẩm là gì

hợp chất MX2. Trong phân tử MX2 có tổng số hạt cơ bản là 140 và số hạt mang điện nhiều hơn số hạt không mang điện là 44. Số khối của x lớn hơn số khối của M là 16. Xác định số p,n,e của X và M

Cho 4,8g Mg tác dụng hết với 200ml dung dịch HCl

a, Viết phương trình và tính khí Hidro thu được ở điều kiện tiêu chuẩn

b, Tính nồng độ phần trăm của dung dịch axit đã dùng 

Giá trị nhỏ nhất, lớn nhất của y=sinx + cosx - 3

Giải giúp cho mik vs ??