1. Bạn có khỏe không?

\(\Rightarrow How\) \(are\) \(you\) \(?\)

\(\)2. Bạn tên gì?

\(\Rightarrow What\) \(is\) \(your\) \(name?\)

3. Họ tên bạn là gì?

\(\Rightarrow What\) \(is\) \(your\) \(full\) \(name?\)

4. Vào thời gian ranh bn làm gì?

\(\Rightarrow What\) \(do\) \(you\) \(do\) \(in\) \(your\) \(feer\) \(time?\)

\(A=1-2-3+4+5-6-7+8+...+2017\)

\(=\left(1-2-3+4\right)+\left(5-6-7+8\right)+...+\left(2013-2014-2015+2016\right)+2017\)

\(=0+0+...+0+2017\)

\(=2017\)

\(\dfrac{1}{15}+\dfrac{1}{35}+\dfrac{1}{63}+\dfrac{1}{99}+\dfrac{1}{143}+\dfrac{1}{195}\)

\(=\dfrac{1}{3.5}+\dfrac{1}{5.7}+\dfrac{1}{7.9}+\dfrac{1}{9.11}+\dfrac{1}{11.13}+\dfrac{1}{13.15}\)

\(=\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{11}+\dfrac{1}{11}-\dfrac{1}{13}+\dfrac{1}{13}-\dfrac{1}{15}\)

\(=\dfrac{1}{3}-\dfrac{1}{15}=\dfrac{4}{15}\)

Ta thấy:

\(9^n\) luôn có tận cùng là \(1;9\)

\(\Rightarrow9^n+1\) luôn có tận cùng là \(2;10\)

\(\Rightarrow9^n+1⋮̸100\)

1.You must cross the road \(..with..\) care.

2. Look \(..at..\) that boy \(..in..\) a motorbike. He is going \(..down..\) this street. He's travelingtoo last.

3. Who are you waiting \(..for..\), Hoa?

4.My brother and I are loading the truck \(..with..\) chairs and desks.

5. Bi is eating his lunch. What \(..about..\) Tony?

6. Bi and Tony are \(..in|on\) the plane. They are flying \(..over..\) moutains.

7. Is Mr. Tom arriving \(..at..\) the airport?