Ablank is a pure substance that can’t be broken down into simpler substance by chemical or physical means.

element

An element is a pure substance that cannot be separated into simpler substances by chemical or physical means.

today we'd use social media to quickly spread a controversial idea, but in the eighteenth century, the printed pamphlet was highly effective. and thomas paine took full advantage of it. on january 9, 1776, when paine published his pamphlet, "common sense," he wanted to push the american people toward independence from britain. it ultimately ignite the american revolution. thomas paine argued that the monarchy was evil and should be rejected as a form of government. to underscore his point, he cited the bible to argue his case -- in judges 8: 22-23: "the israelites said to gideon, 'rule over us, you and your son and your ' gideon told them, 'i will not rule over you. the lord will rule over you'" (nrsv).

quite an interesting way to teach topic sentences, because the answer to this question is the best definition of a topic sentence that one can present, it is as if answering the questions taught you how to do it, this is some real teaching, it is terribly well-done.

the topic sentence in this paragraph is:

topic sentences writers stay on track and keep a paragraph from becoming an aimless collection of sentences about an idea.

which incidentally tells you what a topic sentence should be.