1. Cho hình chóp S.ABCD có đáy ABCD là một hình thang với đáy AD= a bà BC=b. Gọi M,N,P lần lượt là trung điểm các cạnh AB,CD,SB

a, Tìm giao tuyến của hai mp (ADP) và (SBC)

b,Tìm độ dài giao tuyến (ADP) và (SMN) nằm bên trong hình chóp

2.Cho hình chóp S.ABCD có đáy là hình thang với đáy lớn AB.Gọi I,J lần lượt là trung điểm của AD,BC và G là trọng tâm của ΔSAB

a, Tìm giao tuyến của (SAB) và (IJG)

b,Xác định thiết diện của hình chóp với mp(IJG). Thiết diện là hình gì? Tìm điều kiện đối với AB và CD để thiết diện là hbh.

1. Cho hình chóp S.ABCD có đáy ABCD là hình thang. Một mp (anpha) cắt các cạnh SA,SB,SC và SD lần lượt tại các điểm M,N,P,Q . Giả sử α = (IBC) giao (IAD) và Δ ⊂ (α). Chứng minh MQ//NP//AB//CD

2.Cho hình chóp S.ABCD có đáy hình thang AD//BC. M là một điểm di động trong tứ giác ABCD.Qua M vẽ các đường thẳng song song với SA,SB cắt các mặt (SBC) và (SAD) lần lượt tại N,P

a,Nêu cách dựng N,P

b,Tìm tập hợp M sao cho MN.NP lớn nhất

3.Cho hình chóp S.ABCD có đáy ABCD là hbh. Gọi I,J lần lượt là trọng tâm các tam giác SAB và SAD, M là điểm trên cạnh SA sao cho MA=2MS. Xác định thiết diện của hình chóp với mp (MIJ)

Sửa lỗi sai:

1. Could you help me doing this job? I don't know how to get it started.

2. Why don't you stop and tell me why you always avoid to meet me?

3.He doesn't allow me smoking in his house because he believes smoking is harmful to health.

4. I didn't have any money paying him so I had to ask for my father's help.

5.The poor man was unable discovering who had thrown stones at him.

6.I feel my heart to beat quickly whenever I meet her.

7. Fertilizers are used primarily to enrich the soil and increasing yield.

8. Why don't you help each other studying for the final exam.

9.The doctor advised doing exercises, drinking milk and do not smoke.

10.Try to don't keep interrupting the speaker this time.

1. Al of the farmers are asking ''When is this drought going to end?''

->............

2.''I don't like my job very much'' said her cousin

->Her cousin admitted that ............

3.He said''I must be at airport at 6a.m tomorrow''

->He told his daughter.........

4.He siad''The sun rises in the East''

->He said..............

5.The teacher asked all of the students''Do you understand what I am axplaining?''

->The teacher asked all of the students............

6.''My father is a businessman.My mother is an engineer''

->He said that....................

1. A car usually becomes______without any gas in the tank

A.useful B.usable C.useless D.used

2.You can rely on Nam since he is very_________person

A.thoughtless B.thinking C.thinkable D.thoughtful

3.There's nothing______in that terrible apartment

A.valueless B.invaluable C.valued D.valuable

4.It's very_____of you to cross that busy streeet without paying attention to the traffic

A.careful B.cared C.careless D.caring

5.Having spent nearly all his life in the countryside, Mr Long finds this _____to living in any big cities

A.preferable B.preferred C.preferential D.preferring

6.Nothing can be cultivated on that____piece of land

A.treeful B.treetop C.treeless D.tree house

7.That inexperienced teacher doesn't seem____enough to cope with the excellent students of this gifted clss

A.competent B.competitive C.competing D.competitional

8. My mother is a very well____woman.She can always find what she needs almost immediately

A.organizable B.organizational C.organic D.organized

9. Faster is the only____form of the adjective fast

A.comparable B.comparative C.comparing D.compared

10.Those two talkative girls have had their____chatter for nearly two hours without any intervals now

A.continual B.continue C.continueable D.continuing

1.''Did you enjoy your trip?'' asked Tom

-> Tom asked me...............

2.She asked him''Who bought i give the message to?''

->She asked him...............

3. Nancy asked''Have you seen my new grammar book?''

->Nancy wanted to know..................

4. ''Have you finished the above sentences?'' asked his friend

-> His friend asked him.......................

5. John asked ''Who would I give the message to?''

John asked me................

1.''I saw Tom's sister, who was really nice,at Helen's party last weekend'', she sai

-> She told me that........

2. Bob asked '' Where is Alice''

->Bob wanted to know..........

3.''Why is the sky blue?'' my three-year-old asks

->My three-year-old son often asks me............

4. My mother aksed''Why are you tired?''

->My mother wondered............

5.The worker said '' When will the final decision be made?''

-> The worker wanted to know...............