The following is the answer—the retyped sentence as per the directions in the "question".
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<span>In an effort to realize his dream, DUNCAN, an aspiring astronaut, spends hours studying to prepare for his college entrance exams.
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Answer to the second part of the question: The noun to which the appositive refers in the above sentence is: "astronaut".
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{Additional note: the "appositive" in the [rewritten] sentence is "Duncan". "Duncan" (name of student and prospective astronaut) is the "appositive"—in the form of an "appositive noun" [as opposed to an "appositive phrase".]}.
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The pollution of the Kathmandu Valley is believed to be out of control by the environmentalist.
<h3> Or it may be </h3>
It is believed that the pollution in Kathmandu Valley is out of control by environmentalist
In my life for the first time [and,] the image made me believe [of] my mother that I could change [were] the way things *were*.
remove and & of because it makes no sense in the context of the sentence and move were to the end of the sentence.
I’ll change math ,because it’s hard but not that hard .
