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I have to make a toic sentence based on the following paragraph. And this is my topic sentence. What do you think? I am trying to sound my topoic sentence more formal. But I am not sure. Can you help me?

My topic sentences.

There are difference between American eucation system and European education systems.

Amercian education systerm differ from european eudcation system/

In European universities, students are not required to attend classes. In fact, professors in Germany generally do not know the names of the students enrolled in their courses. In the United States, however, students are required to attend all classes and may be penalized if they do not. Furthermore, in the European system, there is usually just one comprehensive examination at the end of the students' entire four or five years of study. In the Americansystem, on the other hand, there are usually numerous quizzes, texts, and homework assignments, and there is almost always a final examination in each course at the end of the semester.
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Not that it relates to your topic sentence, but factually, it's entirely inaccurate to say that all universities in the US require attendance in classes.

To continue with Ed's advice, without restating everything in the paragraph, can you summarize the differences?
Comments  
The paragraph provides information to allow a little deeper analysis

than to say, simply, that the systems are different. That is, it is not
enough just to say the systems are different.
Think of a way to summarize those essential differences.
Students: Are you brave enough to let our tutors analyse your pronunciation?
 BarbaraPA's reply was promoted to an answer.

In European universities, students are not required to attend classes. In fact,
professors in Germany generally do not know the names of the students enrolled in
their courses. In the united states, however, students are required to attend all classes
and may be penalised if they don’t. furthermore, in the European system, there is
usually just one comprehensive examination at the end of the students’ entire four or
five years of study. In the American system, on the other hand, there are usually
numerous quizzes tests, and homework assignments, and there is almost always a final
examination in each course by the end of the semester.