阅读短文,选择合适的答案。
Jim and Ted are twin brothers. They look the same. They are English. They are eleven. They are in No.15 Middle School. They are new students in Class One, Grade One. Jim sits in Row One. Ted sits in Row Three.
读下图,回答题。图中反映出众多的岛屿和深入内陆的狭长海湾,形成这种海岸的最主要原因是( )
育种工作者使用射线处理农作物的种子,再从中选出优质高产的新品种.这种育种方法能够成功,从根本上是因为改变了农作物的( )
38-17=____
48+52=____
46+28-13=____
下列选项不是我们这学期的课本是( )。