单项选择题
A.about B.in C.into D.by
A. Mr. Johns wasn’t at home B. the cows fed themselves C. Mr. Johns had feed the cows in the morning D. they find it difficult to feed cows
A. that the universe is so large that we cannot imagine it B. where the planets in the universe came from C. how the high mountains were formed on the sun D. why the tides over the surface of the sun were so powerful