Red: My corrections

Blue: My comments

Pray for them!

On April 20th, there is an earthquake in Lushan mountain of China.

On April 20th, 2013, an earthquake occured in the Lushan mountain region of China. 

M any buildings collapsed. Many people hurt and died. Many people lost their family and home. They were homeless . They were very sad.

Many buildings have collapsed from the devastation. Hundreds of people have died and thousands of people have been injured. Thousands more have lost their homes and have been in mourning over the loss of their loved ones. 

You do not need to add in "They were homeless" because you already said that "Many people lost their homes" and it is already assumed. I also wrote a new sentence to make it sound better.

But they are strong. They brave to face everything . A difficult one, p plus support. I believe unity is strength .

However there is strength and courage during this difficult time. I believe strength can be found through unity. 

Rewrote these sentences to make them sound better. 

They are not alone and cold because the chinese was with them together.

They are not alone in the dark or lost in the cold because the rest of China was with them.

Made the sentence sound better and little "metaphoric" sounding. 

The government will rebuild their home.

The government will rebuild the houses and buildings destroyed by the earthquake.

Everything will be ok.Best wishes to them.

Everything will be all right. I am wishing and hoping for the best.

I hope you can understand my comments. Hopefully there will be recovery in that region of China.