菠菜浸泡在清水中,清水不变色;用开水浸泡菠菜后,水会变成绿色。这是因为开水损伤了菠菜细胞的什么结构?
A:细胞膜
B:细胞壁
C:细胞质
D:细胞核
下列叙述中,正确的是( )
A
⑴Who are they? ____
⑵Where did you live?____
⑶Is this your grandpa?____
⑷Did he learn Chinese ?____
⑸What's he doing?____
B
A.Yes, it is.
B.They are my grandparents.
C.He's reading a book.
D.No,he didn't.
E.I lived in a small house.