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Over-use of "to be" tends to set off passive voice by connecting two entities which are essentially equal. Part 10a above illustrates an exception to the rule, in conditions where passive voice is most popular and types of "to be" are unavoidable. There are advantages to being bald. Passive voice weakens the motion of a sentence by distancing the motion from the subjects performing the motion. In these circumstances, where lively voice might tend to bury the lede, you may prefer passive voice because it places the key information first. Many cultures worth verbal effectivity and directness; others might feel that this style is simply too blunt or even insulting. Not everyone reads or understands text content material at the identical level, even when introduced clearly and simply. These present an easy manner for users to look at the content structure and, if desired, soar on to content of interest. It's my opinion that the reason that was given by the instructor was delivered in a way that was not transient enough to be fascinating and was not understood by the class.