Viết lại câu :

His business is going badly- he will have to stop doing it soon. ( close )

Viết lại câu giữ nguyên nghĩa :
1. It isn't essential for students to wear uniforms today. => Students .....................
2. My best friend will leave for Bangkok tomorrow. => I wish .....................
3. He could not afford to buy the car. => The car is .....................
4. Quyen will be sixteen next week. => It is Quyen's .....................
5.When did you start to listen to classical music ?. => How long ..................... ?
6. He hasn't been back to his hometown for over 10 years. => It's .....................
7. What a pity! There is a lot of pollution in the air here. => We wish .....................

Nylon was invented (1) the early 1930s by an American chemist, Julian Hill. Other scientists worked with his (2) and finally on 27 October 1983, Nylon was introduced to the world. It was cheap and strong and immediately became (3), especially in making of ladies' stocking.
During the Second World War, the (4) present for many women was a (5) of nylon stockings, but mor importantly, it was used to make parachutes and tyres. Today, nylon (6)in many things: carpets, ropes, seat belts, furnture, computers, and even spare parts for the human body. It has (7) an important part in our lives for over 50 years. Next year about 36 milion tons of it will be manufactured.

Cho \(\Delta ABC\) có góc A = 90 độ, kẻ đường cao AH và trung tuyến AM, kẻ \(HD\perp AB,HE\perp AC\) biết HB = 4,5cm; HC = 8cm.
a, Chứng minh : \(\widehat{BAH}\) = \(\widehat{MAC}\)
b, Chứng minh : \(AM\perp DE\) tại K
c, Tính độ dài AK

Cho 300ml dung dịch \(Ba\left(OH\right)_2\) 1M tác dụng với 200ml dung dịch HCl 3,5M.
a, Tính khối lượng của chất dư.
b, Tính nồng độ mol các chất trong dung dịch sau phản ứng, giả sử thể tích dung dịch không đổi.

Cho 5g hỗn hợp 2 muối là \(Na_2CO_3\) và NaCl tác dụng với 200ml dung dịch HCl ta thu được 448 ml khí (ở đktc)
a, Tính nồng độ mol của dung dịch axit HCl
b, Tính thể tích dung dịch HCl đã dùng ( Giả sử khối lượng riêng của dung dịch HCl là 1,25g/mol )

Phân biệt các chất sau : KOH, HCl, H2SO4, BaCl2
giúp với ạ :<

Viết lại câu giữ nguyên nghĩa :
1. I strated our journey early in order to arrive at the destination on time. (set)
2. I am excited about going to Ha Long Bay this weekend.
=> I am looking ........................
3. I had to refuse their invitation to take part in the trip since I was ill. (because of/turn)
4. She earned enough money from selling fruit on the streets to live. (lived)
5. They decied to go there in spite of the bad weather. ( although/but)
6. I last did the gardening last weekend.
=> I haven't .......................
7. We have to follow more than 10 tages in order to make a conical hat. (so that)
8. She came into the room at the time I was having a bath.
=> While ..................

Viết lại câu giữ nguyên nghĩa :
1. We can't swim in this part of the river because of highly polluted water. (as/so)
2. Two cars still pass each other despite the narrow road. (although/but)
3. In spite of having to work the next day, Tom watched films on DVD till midnight. (even though)
4. I'm frightened by horror films; however, I enjoyed watching them. (though/in spite)
5. Lan often attends English Speaking Club to practice speaking English. (so that)
6. Please arrive early for us to start the meeting on time. (so that)
7. They set off early so that they could reach the village before night. => They set off in order to .....................
8. My father still hasn't really recovered from the death of my mother. (gotten)
9. I am thinking with pleasure about going to Da Lat next week. (forward)
10. Nam invited me to his party but I refused his invitation. => I turned ...............
11. Do you have a good relationship with your elder brother ? (get)

Ở người, gen A quy định mắt đen trội hoàn toàn so với gen a quy định mắt xanh. Xác định kiểu gen, kiểu hình của P và viết sơ đồ lai. Làm theo các bước sau :
Bước 1: Xác định kiểu gen của bố mẹ (P)
Bước 2: Viết sơ đồ : P, G, \(F_1\), \(G_{F_1}\), \(F_2\)
Bước 3 : VIết kết quả tỉ lệ kiểu gen, kiểu hình