A:that
B:a
C:which
D:who
取一段带叶的杨树枝条,将下端插入滴有红墨水的水中,过一段时间取出枝条,进行纵切.发现变红的部位是( )
选出不同类别的单词。
(____)1. A. plate B. how C. cake
(____)2. A. some B. many C. how
(____)3. A. is B. one C. three
(____)4. A. one B. a C. an
(____)5. A. you B. they C. this