My encouragement

One thing I keep for a long time.  Can you guess what this is?  Oh... Composition is my secondary school's assignment.  Why I keep it for a long time?  It is because, all of these composition scored a high marks.  Until now I can’t believe I can write such a high quality and structure. 
This is the encouragement of me.  Every time I read this assignment. I think in the past I can wrote and scored high marks.  How come I have no confident to write any english within my environment?

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One day I fell asleep on the MTR and when I woke up, the train was empty.  I got off the train, ran out of the station and saw that all the streets and the buildings were empty too.  I couldn’t see anybody at all.  The sky was a stretch of dark and covered by a thick blanket of grey clouds.  This town was like a ghost town.
Suddenly, silence was broken by a car.  My eyes were blinded by the dazzling search light from the sky.  I stood stone still and my heart was trembling.  What happened? I puzzled!
The driver took out an automatic machine gun.  I near died of fear and my heart was beating faster and faster like a drum.  I wanted to escape, but my legs were just like pillars sticking firmly.  I lost my consciousness and dropped onto the floor.
When I woke up, I felt a pain in my head.  Standing in front to me was a girl wearing a sweet smile on her face.  She had a long wavy hair and elegant body.  She was called Emily.  ‘What is going on?  I asked in a trembling voice.’
She began to explain, ‘the whole town is full of virus, so all the people will die.’  I don’t believe that.  ‘Stop your joke!’  I was angry running out of the house outside the door was the killer.  I believed what she said.  What should I do?  How could I escape?  Would my life come to the end?
She gave me an automatic machine gun.  She said “you are my hero”.  Let’s kill him to save our life.  Then I was running out of the house.  At that moment, the beam pierced into her body.  I rushed to hold her up.  She said, ‘Be strong! Be my hero!’  Her face was as white as a sheet.  Her whole body was as cold as ice.  She was catching her breath hard before she lost consciousness.  She closed her eyes forever.  No! No!  Please don’t die.  I screamed with tears creeping out of my eyes.  I could not control my emotional outburst.
I got on the MTR and killed all of the killers.  I screamed…

I woke up and found all other passengers staring at me in great bewilderment.  I was so embarrassed to find that it was only a dream.  All my courage shrank back to timidity.  At that time, a charming girl who looked like Emily in my dream gave me a note before she got off.  It read, “Well done, my hero!”