Spooky Halloween Story - short story

Hi, it's my English homework, I had to write a short story entitled "Spooky Halloween Story".
Words limit: 200-250. It has to contain two sentences "When she opened the door, she immediately knew there was someone in her house." and "Unfortunately it was too late."
It will be gratefull if someone can show me all the mistakes I had made in this essay. :)

Spooky Halloween Story

When she opened the door, she immediately knew there was someone in her house. She asked “Is there someone?”, but no one answered, so she went to the kitchen and started making supper. While she was chopping tomatoes, she heard knocking upstairs. The knife fell out from her hand. She picked it up with shaking and went to the stairs. The noise was going from bathroom in the end of the hall. She turned on the lights and went straight on, holding raised knife. The door was ajar. She was very frightened, her heart beating was very loud. She opened the door and turned on the lamp very quickly. For her surprised there wasn’t anybody in the bathroom and the noise blew over. She was going through the hall. When she stood on the first step, someone said “Hello”. She screamed very loudly and she started falling down the stairs. On the floor she realized, her arm had broken. She was groaning with pain. She looked up and saw a man with a pumpkin head. He was holding bloodstained knife. The man was going to her.

“What do you want? Why do you want to kill me?”- she asked.

“It’s your Halloween present (gift).” – he answered laughing.

She was trying to get to the main door. She stood up crying and held the handle, but unfortunately it was too late. He caught her and said “Trick or treat!”, stabbing her stomach. She fell down, spitting with blood. While the man was going out he said for goodbye “ Happy Halloween!”.

[QUOTE=Arbe;817614]Hi, it's my English homework. I had to write a short story entitled "Spooky Halloween Story".
Words limit: 200-250. It has to contain two sentences "When she opened the door, she immediately knew there was someone in her house." and "Unfortunately it was too late."
It will be grateful if someone can show me all the mistakes I have made in this essay. :)

Spooky Halloween Story

When she opened the door, she immediately knew there was someone in her house. She asked “Is anyone there?”, but no one answered, so she went to the kitchen and started making supper. While she was chopping tomatoes, she heard knocking upstairs. The knife fell out from her hand. She picked it up with shaking hands and went up the stairs. The noise was coming from the bathroom at the end of the hall. She turned on the lights and went straight on, holding a drawn knife. The door was ajar. She was terribly frightened; her heart was beating wildly. She opened the door and turned on the lamp very quickly. Much to her surprise there wasn’t anybody in the bathroom and the noise stopped. She hurried back to the stairs. When she stood on the top step, someone said “Hello”. She screamed very loudly and fell down the stairs. Sitting on the floor groaning with pain she realized, her arm had broken. She looked up and saw a man with a pumpkin head. With a bloodstained knife, the man was going towards her.

“What do you want? Do you want to kill me?” she asked.

“It’s your Halloween gift.” he answered with a horrible laugh.

She tried to get to the front door. She stood up crying and held the handle, but unfortunately it was too late. The man caught her and said “Trick or treat!”, stabbing her stomach. She fell down, spitting with blood. While the man was going out he said for goodbye “Happy Halloween!”

Thanks a lot. ;)