第二节：语法填空 (共10小题；每小题1.5分，满分15分)

I have a 12-year-old son who is kind and helpful. And he is showing great interest  26  growing plants. I have been helping him plant flowers, vegetables and just plants in general since spring arrived.

When  27  (plant) a bunch of flowers one Saturday afternoon , I found that there were two flowers  28  (leave) in my son’s basket. My son decided to take them to the little house next door  29  an elderly woman lived by herself and didn’t seem to have much company. I watched him as he went up to her door, rather  30  (hesitant ) because he didn’t know her, and he quietly left the flowers  31  her doorstep so that she would get  32  the next time she went outside.

The next morning we were pleased to find that she  33  (plant) the flowers in a pot by the door. They looked really beautiful.  34  it was a small thing , it was important as my son has learnt to do good for  35 .  He said to me, “It feels really good to do things for other people.” 

软性填料的孔隙率是（）。

A.>96%

B.>97%

C.>98%

D.>99%