根据以下材料，回答题
Sometimes I really doubt whether there islove between my parents. They are very busy working to 16 the family. They don′t act in the 17 ways that I read in books or I see on TV.18 flowers to each other onValentine′s Day is even more 19.One day, my mother was sewing a quilt (床单). I 20 sat down beside her and lookedat her. "Morn, is there love between you and Dad " I asked her in a21 voice.
My mother stopped and raised her head with 22in her eyes. She didn′t answer immediately.
Then she 23 her head and continued tosew the quilt. At last my mother said:
"Susan," she said, "Look atthis thread. Sometimes it appears, but most of it 24 in the quilt.
The thread really makes the quilt strong and25. If life is a quilt, then love should be a 26. It can hardly beseen anywhere or anytime, but it′s really there. Love is 27."
The next spring, my father suddenly got sickseriously. When they returned from the hospital, mother looked rather pale andit seemed 28 of them had a serious illness. Everyday in the morning and dusk, my mother helped my father 29 slowly on the country road. My father hadnever been so 30.
Along the country road, there were manybeautiful flowers, green grass and trees. The sun gently glistened through theleaves. All of these 31 themost beautiful picture in the world.
"Dad, how are you feeling now " Iasked him one day.
He said gently. " 32, I just like walking withyour morn. I like this kind of life." 33 his eyes, I know he lovesmy mother deeply.
34 I thought love meant flowers, girls andsweet kisses. But from this 35, I understand that love is just a threadin the quilt of our life. Love is inside, making life strong and warm.
A.process
B.way
C.matter
D.experience