1 . During my last winter holiday, I went to ________ countryside with my father to visit my grandparents. I found a big change there. （用适当的词填空）

2 . (2018·全国Ⅱ)Corn production has jumped nearly 125 percent over __________ past 25 years, while rice has increased only 7 percent.

3 . Of ________ nineteen recognized polar bear subpopulations，three are declining，six are stable，one is increasing，and nine lack enough data. (用适当的词填空)