国际经济合作与国际贸易的共性有（）。A、都是国际经济交往的重要形式 B、都与生产要

     Learning experience happens to us throughout our lives. Not long ago I had one that I would like to
   1     .
     I was going to Marblehead with my sailboat team. The team was racing down the highway at 85
mph       2  we realized we were    3    . Luckily, we saw a rest area ahead. I had a brand-new $ 20 bill.
I was so    4    because I had never had that kind of cash before. But spending it on   5    seemed like
throwing it away. We all rushed into the pizza line.   6     I got a pizza and a drink, and walked to my
table. About halfway through the meal, I    7     I had not actually handed any money to the cashier . I
had just   8     out, and nobody had noticed. I felt terrible.
     My conscience opened its mouth and swallowed me in one big bite. I couldn't    9      over it. I just
couldn't go back to the cashier and    10     for my stolen pizza. I was so upset that I    11    to give
myself  the pleasure of an ice cream in    12     that someone would say "Hey, Jeff, why don't you use the
change    13    the pizza instead of that nice, new $ 20 bill?" I was not so    14     of my cash now.
     For the next two years, whenever I was    15      of the "Pizza incident", I would say to myself "Don't
think about it any more".
     I have learned two things from this    16     . Maybe I was a fool for   17      in to my conscience, and
being too stupid to appreciate a   18     pizza. But the real lesson is that even if you get away from what
you have done, your conscience will   19      up with you.
     This reflects the saying "A coward dies a thousand deaths, a hero dies one." I was a coward and
have felt terrible about that incident at least a thousand times. If I had been a   " 20 "   and gone back to
pay for the pizza, I would have felt a little uncomfortable about it only once, or maybe twice.