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Re: A full account of the complexities of sleep, sought
[#permalink]
14 Nov 2017, 04:14
Explanation
Sleep is important, or relevant, to your daily life, making pertinent the best word for the first blank. Don’t be misled by the fact that you don’t fully understand sleep into choosing mysterious or obscure; both are trap answers (being ignorant about a mysterious or obscure topic is hardly “fascinating”).
It is also grammatically incorrect to call a topic mysterious or obscure to your daily life. Regarding the second blank, the expression “at once X and Y” indicates at least a loose contrast, so you need something that could contrast with fascinating. The clue “so ignorant” is a good indication that what you want is deeply humbling. Don’t fall for the trap answer fully impenetrable. While the topic of sleep is presented as somewhat impenetrable (that is, hard to understand), the blank is not describing sleep, but rather your ignorance about it.
Pertinent, deeply humbling.