某公路上简支梁桥，标准跨径为15m，计算跨径为14.6m，梁桥由5片主梁组成，主梁高

     "You will never walk again. You will have to use a wheelchair. " I heard his   1   fall heavily on my
ears, numbing my soul. If I had never felt hopeless before, I felt hopeless then.
     The car accident had left me unconscious. When   2  , I found both legs in casts (石膏). While I had
other serious injuries, my   3   were my first concern. Working as a special needs teacher and busy and
active by nature, I couldn't imagine being   4   in a wheelchair.
     Lying in my bed, I wondered how I   5   give my ten-year-old son hope that mom would  6  . He'd
been cheerful on every visit, but I saw   7   in his eyes. He needed the ray of hope that I would not be in
a wheelchair forever.
     Just maybe, I thought, I could use this experience to teach him what to do when   8   strikes.
     It didn't take me long to become impatient with my limited movements and even with the pace (进度)
the doctors were willing to go with me. I was   9   to learn everything they showed me.
     Every night in my private room, as soon as I knew I wouldn't be   10   or discovered, I would move
myself from the bed to the floor,   11   on to the bed rail (床栏杆) for dear life, and slowly putting my
weight  12   my feet. After several weeks of such difficult   13  , my strength and confidence continued
to   14  .
     The time came to share my achievements with the person most   15   to me. One night, when I heard
my   16   greet the nurses at the station, I dragged (拖,拉) myself up. As he opened the door, I took a
few small steps.   17  , he could only watch as I turned and started back to bed. All of the pain, the fear,
and the struggle   18   as I heard the words I had longed to hear, "Mommy, you can walk!"
     I  am now able to walk alone, sometimes using a stick. I am able to take public transportation to shop
and visit friends. My life has been blessed with (有幸得到) many   19   of which I am proud. But none
has ever brought me the satisfaction and joy   20   by those four little words of my son.