If we say that outline should make use of subordination, we mean that HEADINGS SHOULD BE GENERAL WHILE SUBHEADINGS SHOULD BE MORE SPECIFIC.
In the writing process, outline helps a writer to logically and systematically arrange his materials. Each outline is expected to observe four basic principles, which are: parallelism, coordination, subordination and division. The principle of subordination requires that, In order to indicate the level of significance, an outline should use a principal and subordinate headings. Thus, materials should be ordered from general to specific.
<span>C. None but the brave shall enter in.
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Here but is not a conjunction but a preposition itself.
<span>Preposition is a part of speech where the word in a sentence describes the position of the subject or the word being illustrated.</span>
<span>This is an analogy that you need to complete in order to see what the final word should be. So, exciting is an adjective that describes the noun thrill. So, in order to finish the analogy, you need a noun that the adjective difficult refers to. That noun could be ordeal, hardship, trouble, torment, torture, etc. You need a word that means "something difficult," so any of those words could be the correct answer.</span>