不同白冠雀群的鸣声虽然基调相同，但又有各自的“方言”。如果把某个白冠雀群（A）的幼雏（a）移到另一白冠雀群（B）中去，待长成成鸟时，a的鸣声就不同于A鸟群而接近B鸟群，但是如果把白冠雀幼雏（b）移到黄莺鸟群中生活，它却学不会黄莺的鸣声。请回答：
（1）白冠雀幼雏a的鸣声，具有B鸟群的“方言”特点，这是____ 行为在起作用。
（2）白冠雀幼雏b学不会黄莺的鸣声，是因为b与黄莺体内的____ 不同。
（3）同种动物中不同个体的学习能力是____ 的。
（4）上述实验说明，____ 行为是在____ 行为的基础上建立的，也就是说动物学习行为的出现是在____ 因素的基础上。

我的长高方法是挑食、暴饮暴食，不锻炼。（    ）

钢铁制造的船能够浮在水面上，原因在于它____很大。

今年5月，我市发现了首例H7N9禽流感病例．下列对病毒的叙述不正确的是（    ）

阅读下面短文，从各题所给的选项中选出最佳答案。    

    Liu Lin, a student at Chengdu University, made a big decision last August. She decided to take her 93-year-old grandmother from their hometown and to 1 with her in a rented room not far from the university.

    Why did she do so? Because many  2 things happened to her family last year. In March, her grandmother broke her leg. In April, her father passed away. Her mother, plagued(折磨) by these 3 , lost the ability to take care of others.

    This was the only choice for her 4 no one else could care for her grandmother. The old woman's three sons have all died, and Liu Lin couldn't leave5 alone at home where nobody could look after her.

    A room with two beds, a wardrobe(衣柜), a desk and a table is their new 6  in Chengdu. The room costs 600 yuan per month. Liu Lin's younger brother works in the same city and  7 most of his 2,000 yuan salary(工资) supporting the family.

Liu Lin and her brother were brought up by their  8 . Even though she could not read a clock, their grandmother prepared lunch on time every day when they were 9. They think it's their turn to look after her now.

    Liu Lin has  10  a work-study program from the university to help support the family. She reduces help from others. At present, the girl is able to support the family.