Above the land and water _ with a depth estimated to be from 50 to 200 miles.

题目

Above the land and water _ with a depth estimated to be from 50 to 200 miles.
A.a layer of air is
B.
will a layer of air be
C.
a layer of air be
D.
is a layer of air

答案

D 完全倒装句,实际上是A layer of air is above the land and water with a depth estimated to be from 50 to 200 miles.
同样类型：There stands a man.
A man stands there.
英语句子的语序通常是主语在前,谓语在后,这种语序称作正常语序或自然语序.但有时出于语法或达到某种修辞目的(强调、承上启下、平衡等)的需要,要把谓语动词放在主语前面,这种语序称作倒装(Inversion)语序.将谓语动词完全移至主语之前,称完全倒装(Full Inversion)；如果只是把助动词或情态动词放在主语之前,称为部分倒装.