下列物质中，不能用金属跟稀酸反应直接制得的是（    ）

成熟的植物细胞在较高浓度的外界溶液中，会发生质壁分离现象，图a是发生质壁分离图象，图b是显微镜下观察到的某一时刻的植物细胞，请据图回答下列问题：

    I had a busy weekend. On Saturday morning, I 1 up late. At eleven o'clock, I went shopping at a 2. Then I went 3 in a swimming pool. After that, I 4 lunch and then cleaned the house. In the evening, I went out 5 a restaurant with my friends. We 6 a nice dinner and talked a lot.

    7 Sunday morning, I also got up 8. After breakfast, I 9 my grandparents in the countryside by bus. I helped them 10 some clothes and 11 them funny stories. They 12 very happy to see me. I came back 13 at 6 p.m. After dinner, I 14 an interesting book and went to bed 15 about half past nine.