Ingles Topic Sentence

Topic Sentence
The topic sentence is a primarily prescriptive grammatical term to describe the sentence in an expository paragraph which summarizes the main idea of that paragraph. It is usually,but not always, the first sentence in a paragraph. The topic sentence acts as a kind of summary, and offers the reader an insightful view of the writer’s main ideas for the following paragraph. Morethan just being a mere summary, however, a topic sentence often provides a claim or an insight directly or indirectly related to the thesis. It adds cohesion to a paper and helps organize ideas bothwithin the paragraph and the whole body of work at large. Its use is considered standard in the American educational system and most venues of writing mainly because it increases reading accessibility.A topic sentence (also known as a focus sentence) encapsulates or organizes an entire paragraph, and a writer should be careful to include one in most major paragraphs. Although topic sentences mayappear anywhere in a paragraph, in academic essays they often appear at the beginning.

Examples:
Ancient people helped in different ways to develop practical mathematics. 
Among then Egyptian andBabylonian mathematics’ contributions were the most remarkable. Egyptian activities in the mathematical field were as important as the Babylonians´. In Egypt, for instance, the voluminous Nile usedto overflow its banks frequently and this washed away the divisory boundaries. So, the Egyptian people had to re-measure the big areas of land after every flood. They became great expert geometry. Thisaccurate knowledge of the world: the pyramids.
The Babylonians were less advanced in geometry than the Egyptians. Yet, they developed a greater skill with numbers because they were great traders andthey needed to do business successfully. Ancient sailors were as practical as Babylonians and Egyptians. They used the bright sun and the shining stars to find their way when land was out of sight....