We should feel grateful in our heart when we accept anything others sacrifice for us. However, we often unconsciously do the opposite, which may not be regarded as returning kindness with ingratitude, but have the equal power to harm each other. In particular, the closer the relationship is, the more determined we are. Jennifer, my friend Randy's mother, is already over 70, poor eyesight and weak legs. But due to her character, she chose to live alone in the suburbs. No matter how busily Randy works, he would go there to visit her once or twice every week. That day as soon as he parked his car, Randy smelt the delicious smell of meat coming from her mother's house. His mother said, "Your birthday is coming next week, so I'm preparing pork trotters   for you!" Seeing the steaming delicious trotters, he couldn't help complaining, "I don't like these things at all, so fatty." On his way back, he called me, saying that he felt sorry. In fact, he longed to thank his mother and eat up that bowl of trotters. But he felt sorry that it took her too much time and energy. If he didn't stop her strictly, he was afraid the same thing would continue. He would rather not eat trotters any more than have his mother overwork. I understand how he felt exactly. Each of us has done like that. Because of feeling sorry for others' sacrifice, we purposely harden our heart against accepting others' favor and even criticize them severely in order to frighten their goodness away and make them never do that again. This method may work, but it will hurt each other's feelings. It's not wrong logically, but we always neglect another sound deep in our heart: because we're afraid we can't repay them, we're unwilling to shoulder others' goodness. So we reduce its value and refuse it severely. But to destroy others' goodness is also to deny you. According to the author, we sometimes say "no" to others' favor so that   _  .
they can be frightened away they won't continue doing that we needn't repay them later we won't feel sorry for their sacrifice