A Puma

Mrs.Stone had spent the whole morning picking (to pick) blackberries (,) and she felt tired. (,) It was nearly lunch time, so she decided to go home. She was amazed when she heard a noise in the grass,than (she) saw an animal which looked (looks) like cat,but was much (more) larger. ( than cat,) She knew it was not a cat, because (bacause) she saw a trail of dead small animals behind it. The animal suddenly approached (come to) her,and she thought it was going to attack her. (,) She was scared and dropped (droppe) her basket and shouted for help. Hearing the sound, the animal stopped in it's tracks (its step), after which,Mrs.Stone took (taken) up her basket and ran all (alll) the way home. She told her neighbours that she saw a large cat-like animal,but they did not believe her. She also telephoned the police but they did not take her seriously.

You need initial capitals for the title and the start of each sentence, also leaving a gap after each full stop. The sentences are well constructed, but you just need more attention to capital letters.  

a puma

Mrs.Stone had spent the whole morning picking up blackberries,she felt tired,it was nearly lunch time,so she decided to go home.she was amazed when she heard a noise in the grass,then she saw an animal which looked like cat,but more larger than cat,she knew it was not a cat,bacause she saw a trail of dead small animals behind it.the animal suddenly started coming to her,and she thought it was going to attack her,she was scared and dropped her basket and shouted for help.hearing the sound,the animal stopped its step, after which,Mrs.Stone took her basket and ran alll the way home.She told her neighbours that she saw a large cat-like animal,but they did not believe her.she also telephoned the police but they did not take seriously.