Sunspots, vortices of gas associated with strong electromagnetic activity, are visible as dark spots on the surface of the Sun but have never been sighted on the Sun’s poles or equator.
(A) are visible as dark spots on the surface of the Sun but have never been sighted on
(B) appear as dark spots on the Sun’s surface, which have never been sighted on
(C) are visible as dark spots that never have been sighted on the surface of the Sun
The first one is the answer
I am really puzzled that OG say a verb "are" must be inserted into the sentence, but appear is also a verb. What is the reasoning behind it? If I insist on using appear, should it be "...are appear as...."??
Based on accounts of various ancient writers, scholars have painted a sketchy picture of the activities of an all-female cult that, perhaps as early as the sixth century BC, worshipped a goddess known in Latin as Bona Dea, “the good goddess.”
Answer: Using accounts of various ancient writers
Can anyone explain why based on is incorrect?
(A) are visible as dark spots on the surface of the Sun but have never been sighted on
(B) appear as dark spots on the Sun’s surface, which have never been sighted on
(C) are visible as dark spots that never have been sighted on the surface of the Sun
The first one is the answer
I am really puzzled that OG say a verb "are" must be inserted into the sentence, but appear is also a verb. What is the reasoning behind it? If I insist on using appear, should it be "...are appear as...."??
Based on accounts of various ancient writers, scholars have painted a sketchy picture of the activities of an all-female cult that, perhaps as early as the sixth century BC, worshipped a goddess known in Latin as Bona Dea, “the good goddess.”
Answer: Using accounts of various ancient writers
Can anyone explain why based on is incorrect?












