ExA:

1. I am writing to you about the noise caused by Karaoke shop near my house

2.They have played music very loudly , so I can study in the evening and sleep at night

3.They should lower the volume when it is 9pm

4. I am looking forward to hearing from you and seeing how you solve this problem

EXB:

1.Nam got wet because he forgot his umbrella.

2.If we go on polluting the water, we will have no fresh water to use.

3.If you don't throw the stone into water, it won't be sink.

4.If people don't use a lot of wood bulb, many trees aren't cut down.

A/

$1$. I am writing to you about the noise caused by Karaoke shop near my house

$2$. They played music so loudly so I couldn't study in the evening and slept at night

$3$. They should lower the volume when it is 9 pm

$4$. I am looking forward to hearing from you and see how you will solve this problem. Faithfully, Mai...

B/

$1$. Nam forgot his umbrella so he got wet

$2$. We will have no fresh water to use

$3$. If we throw a stone into water, it sinks

$4$. If people didn't use a lot of wood bulb, many trees wouldn't be cut down