Give the correct form of the words in brackets to complete each sentences. 

1. A lot of toy encourage children's...(imagine).

2. The factory has provided cheaper ....lately (produce). 

33. Burning coal is an...(economy) way of heating house. 

4. Gas and oil ...(consume ) always increases in cold weather. 

5. He claimed that his ....(bring up) had caused him to become a criminal.

EX 1: Supply the correct forms of the word in parentheses. 

1. People on the island are very friendly and... ( hospitality). 

2. The polices are interested in the sudden ....(appear) of the valuable painting. 

3. I wrote ... ( end) letters of the application but i got no repply . 

4. The tiger wanted to see the farmer's ... ( wise). 

5. He was....(fool) to say that English is helpness. 

Bài 1 : tìm GTNN của các biểu thức sau : 

a) A=/x^2+4/+2022. 

b)B=/x^2-4/+2022.

Tìm giá trị nhỏ nhất của các biểu thức sau :

a) A=x^2 + 2.y^2 +3. 

b)B= /x-2022/+/x-2021/+/x-2020/

Tìm giá trị nhỏ nhất của các biểu thức sau :

a) A= x.(x+1)+x+2. 

b) B= /x-1/+3

Chứng minh rằng : 

3^n+2  -   2^n+2  +  3^n   - 2^n chia hết cho 10.