Ist das grammatikalisch richtig?

Hallo Leute,

Ich schreibe morgen eine Klausur über Street Art / Guerrilla Art / Banksy und habe mich darauf vorbereitet mit einer kurzen Übersicht, was ich in der Bildbeschreibung nennen möchte; eine Sachtextzusammenfassung von einem Text, den wir im Unterricht durchgenommen haben und mit einem Text über meine eigene Meinung über Street Art. Könntet ihr drüber schauen, ob ich von den Grammatikalischen Regeln im Englischen keine missachtet habe? Ich habe schon gehört, dass zum Beispiel die Meinung über Street Art abgefragt wird, wodurch ich den Text wahrscheinlich 1 zu 1 in der Klausur schreiben möchte. Danke für eure Hilfe

Ps: Ich schreibe die Klausur erst um 16:30 Uhr, deswegen wäre es kein Problem, wenn ihr erst morgen antworten könnt.

English – Description of a Picture
The picture was painted by Banksy in London and shows “a cleaner, who cleans a stone age painting on a street wall”.
Description (At first the locations of the obvious, then the details: colours, small objects, how did he use the background?)
Message (political, philosophic, morally)
Evaluation (good / bad painting / message, effectiveness)

Summary
The newspaper article written by B. O’Neill was published in “The Christian Science Monitor” on 8. January 2007. The article is about a discussion over visual street art and guerilla art, whether they are good or bad.
The text starts with a description of a street art by Banksy. The following are arguments for and against guerilla art. The artists use stencils, slogans, objects and official signs. Their art is of a criminal nature, mysterious and created overnight on walls of buildings without prior warning. This protest graffiti has always a political, philosophical or morale message. These messages encourage thinking.
The structure of the article shows, that the negative arguments are refuted by following positive arguments. Altogether, the writer of the article thinks positive about guerilla art, but he ends with an unfavorable sentence. He has the fear that guerilla art goes mainstream.

My opinion about street art
Street art is of a criminal nature, mysterious and created overnight on walls of buildings without prior warning. This art is made with stencils, slogans, objects and official signs. The “protest graffiti”, guerilla art, has always a political, philosophical or morale message. These messages encourage thinking.
On the one hand, there are people, who might say that street art is vandalism and dirty. These people don’t like graffiti also because it is expensive to clean from walls. They see only the bad street art, the ugly.
On the other hand, there are people, who believe that street art gives life to walls. They see the beauty and the important message in some graffiti. This group walks the streets and thinks about the messages behind of pictures.
To sum up, street art is an important art in our time, which encourages thinking about the politic, moral or philosophic things.

Ich habe mich jetzt selbst rangesetzt und habe selbst ein paar Fehler gefunden und habe eine Bildbeschreibung ergänzt. Ist dies alles grammatisch richtig?

English – Description of a Picture
The picture was painted by Banksy in London and shows “a cleaner, who cleans a stone age painting on a street wall”.
Description (At first the locations of the obvious, then the details: colours, small objects, how did he use the background?)
Message (political, philosophic, morally)
Evaluation (good / bad painting / message, effectiveness)

The picture was painted by Banksy in London and shows a yellow flower and a white painter with a paint roller in hand.
The white painter is on the left-hand side and looks sadly. He sits on a paint can with a paint roller in hand and wears a white cap and a black bib short.
In the centre and on the right-hand side is the big yellow flower, which was created by painter and starts from yellow line of roadside and goes over pavement on the wall (chimney).
The picture criticizes the lack of enthusiasm of the work. No variations are in the most jobs. The workers distract themselves on other thoughts, e.g. fun, flowers, freedom.
I agree the intended message of working. We all live in a world, which bases on money and work. All people, who have a job, will eventually come to the point of boring everyday life after years of work. We search variations in our life. Also, I find that the inclusion of the environment is well implemented.

Summary
The newspaper article written by B. O’Neill was published in “The Christian Science Monitor” in 8. January 2007. The article is about a discussion over visual street art and guerilla art, whether they are good or bad.
The text starts with a description of a street art picture by Banksy. At following, it will call arguments for and against guerilla art. The artists use stencils, slogans, objects and official signs. Their art is of a criminal nature, mysterious and created overnight on walls of buildings without prior warning. This protest graffiti has always a political, philosophical or moral message. These messages encourage thinking.
The structure of the article shows, that the negative arguments are refuted by following positive arguments. Altogether, the writer of the article thinks positive about guerilla art, but he ends with an unfavorable sentence. He has the fear that guerilla art goes mainstream.

My opinion about street art
Street art is of a criminal nature, mysterious and created overnight on walls of buildings without prior warning. This art is made with stencils, slogans, objects and official signs. The “protest graffiti” (=guerilla art) has always a political, philosophical or moral message. These messages encourage thinking.
On the one hand, there are people, who might say that street art is vandalism and dirty. These people dislike graffiti also because it is expensive to clean from walls. They see only the bad street art, the ugly.
On the other hand, there are people, who believe that street art gives life to walls. They see the beauty and the important message in some graffiti. This group walks the streets and thinks about the messages behind of pictures.
To sum up, street art is an important art in our time, which encourages thinking about political, moral or philosophic things.