Descriptive .
it is the sentence that tells you what the paragraph is about but it doesn't have to be the first it can be the last
A lead sentence starts a paragraph. It tells the reader a quick little intro into what you are about to go into in the sentences that follow
I call it the "topic sentence".
Every paragraph should have a topic sentence (which tells what the paragraph is about), several supporting details (sentences that give examples or explain the topic sentence) and a concluding sentence (which wraps it up or leads to the next paragraph.)
A key sentence is usually the first or second sentence of the article. It explains or draws in the reader regarding what the article is about. Then after that it goes on to explain the subject or what the article is about. It is the sentence that draws the reader in. A key sentence in a paragraph tells what the paragraph is all about it may be found at the beginning of the paragraph in the middle,or at the end of the paragraph.
The sentence in a paragraph that summarizes what that paragraph is about
The sentence that states the main idea of the paragraph is called the 'Topic Sentence'.
A topic sentence is a perspective grammatical term to describe the sentence in an expository paragraph which summarizes the main idea of that paragraph.
The topic sentence is the most important sentence - the one that tells you what the paragraph is about. Find that and you've found the topic sentence. WikiAnswers cannot do your entire assignment for you - that's cheating and it's wrong.
Usually the topic sentence is the first sentence in a paragraph. The topic sentence makes a statement about some topic and the rest of the paragraph explains the topic sentence or gives examples of the topic sentence. For example if this was the topic sentence There are three living species of Kiwi all of which inhabit New Zealand. Then this paragraph would probably tell us what the three species are and where they live in NZ.
Generally the topic sentence is the first sentence of the paragraph and the rest of the paragraph explains or gives examples of the topic sentence. The topic sentence can also be the second sentence of the paragraph. This is when the first sentence is a linking sentence that links the paragraph to the previous paragraph. Sometimes the topic sentence can be the last sentence in the paragraph
A sentence that summarizes what the paragraph will be about is the topic sentence.