1.Một Oxit của phi kim X có phân tử khối là 44 đvC . Tìm công thức Oxit trong hợp chất

3. R là hợp chất khí của Nitơ với Hiddro có phân tử khối là 17 đvC . Xác định công thức phân tử của khí R

Oxit A của Nitơ có phân tử khối là 46,11 đvC . Tìm công thức Oxit A

chứng tỏ rằng giá trị của các biểu thức sau ko phụ thuộc vào biến

x(x^2 +x+1) - (x+x^2 +1)-x^3

phân tích 1 hợp chất người ta thấy có thành phần phần trăm khối lượng là 40%Cu , 20%S và 40%O . Em hãy xác định công thức phân tử của hợp chất . cho biết trong phân tử hợp chất chỉ có 1 nguyên tử Cu

Unit 9: Passive voice
Explanations:

II. Choose the most suitable tense:
where is the carpet? It *is cleaned/ cleans / is being clearned*

III. Rewrite each sentence, putting the verb underlined in the passive where this is possible:
1. I really like this hotel.
2. People ate most of the food at the party.
3. Jane won the poetry competition.
4. Peter’s new car cost oner $20,000.
5. Martin always wears casual clothes.
6. One of our visitors lost this cigarette lighter.
7. They haven’t decided the exact time of the match yet.
8. Most of the guests had left the hotel by midday.
9. Some parents read to their children every night.
10. This bike belongs to my sister.
V. Complete the second sentence so that it has similar meaning to the first, using the word given (Two to five words):
1. Last Thursday we appointed a new marketing manager.
*was*
A new …………………………………….. last Thursday.
2. Smith Lid are supplying our company with furniture.
*supplied*
Our company …………………………………………… by Smith Lid.
3. William the Conqueror built the castle in the 11th century.
*by*
The castle …………………… William the Conqueror in the 11th century.
4. No decision has yet been made.
*decided*
Nothing …………………………. yet.
5. People believe that someone murdered Jenkins.
*was*
It ………………………………… murdered.
6. Your hair needs cutting.
*get*
You ought ……………………….. cut.
7. The police were following the suspects.
*were*
The suspects …………………………….. police.
8. No – one has seen Peter since the day of the party.
*been*
Peter ………………………………….. the day of the party.
9. We put a notice about the trip on the notice board yesterday.
*was*
A notice ……………………………… up on the notice board yesterday.
10. People think that an apple a day is good for you.
*to*
An apple a day ……………………..for you.
VI. Rewrite each sentence so that it contains a form of have something done. Do not include the agent.
1. A painter painted our house last month. -> ……..
2. The hairdresser is cutting my hair this afternoon. ->
3. Someone has stolen my motorbike. ->
4. The dentist has taken out all of Ricky’s teeth. ->
5. I ahven’t been to the car-wash for a long time. ->
6. The men are coming to put in the new central heating on Saturday. ->

7.Someone broke Harry's nose in a flight ->.....

8. Isn't it time someone fixed your TV?->

9. Helen's publishers have just publishers her book ->

10. The police towed away Nigerl's car->