英语单选The mountain,which is very high ,looks grey ____the sky.

英语单选
The mountain,which is very high ,looks grey ____the sky.
A.over B.under C.against D.for
-Hello,can you find me a boy?
-______
A.Centainly,he is in the classroom
B.What`s his name?
C.What clothes is he wearing?
D.Is he tall or short?
these flowers must be watered___.
A.every other day
B.each other day
C.every of two days
D.each of two days
--Tom fell off his bike and hurt himself badly.
--______was that?
A.How soon
B.How long
C.How long ago
D.For when