阅读短文，根据短文内容，在空白处填入一个适当的单词，必要时进行词形变化。
(A)
Bags of Love
Last year, I was assigned to work at an office near my mother's house, so I stayed with her for a month. During that time, I helped out with the housework and contributed to the groceries.
After less than a week, I started noticing that the groceries were running out pretty quickly — we were always suddenly out of something. ____ (wonder) how my mum could consume them so quickly, I began observing her daily routine for two weeks. To my surprise, I found that she would pack a paper bag full of canned goods and head out every morning at about nine. Eventually, I decided to follow her and ____ happened truly amazed me. She was taking the food to the refugee camp, in ____ she distributed it to children.
I asked around and found out that my mum was very well known in the area. The kids were very friendly with her and even looked up to her as if she were their own mother. Then it hit me —why would she not want to tell me about what she ____ (do)? Was she worried about how I would react or that I would stop ____ (buy) the groceries if I found out?
When she got home, I told her about my discovery. ____ she could react, I gave her a big hug and told her she didn't need to keep it a secret ____me. She told me that some of the children lived with an older lady in a shelter while others slept on the streets. For years, my mum has been helping out by giving them whatever food she could spare. I was so impressed by ____ selfless she was.
和圆 
的交点为 
、 
，求弦 
的长．