It seems that ________ is no set amount of time that everyone needs to sleep each night.

It seems that ________ is no set amount of time that everyone needs to sleep each night.

• A. that
• B. there
• C. this
• D. these

Answer: (B)

Using there as a dummy subject to introduce existence is what this sentence needs. It seems that there is no set amount of time that everyone needs to sleep each night. Here, there doesn’t point to a specific object; instead, it acts as a placeholder subject so the verb can link to the noun phrase that follows—no set amount of time. That noun phrase is the real information being stated, while there being-structure just introduces its existence. Other options wouldn’t fit the grammar or the meaning. That would awkwardly try to refer to something previously mentioned, or behave like a demonstrative pronoun rather than an existential starter. This and these don't function to introduce an existence in this context, and this sentence needs an existential “there” to sound natural and correct.

Using there as a dummy subject to introduce existence is what this sentence needs. It seems that there is no set amount of time that everyone needs to sleep each night. Here, there doesn’t point to a specific object; instead, it acts as a placeholder subject so the verb can link to the noun phrase that follows—no set amount of time. That noun phrase is the real information being stated, while there being-structure just introduces its existence.

Other options wouldn’t fit the grammar or the meaning. That would awkwardly try to refer to something previously mentioned, or behave like a demonstrative pronoun rather than an existential starter. This and these don't function to introduce an existence in this context, and this sentence needs an existential “there” to sound natural and correct.