About ten men in every hundred suffer from color-blindness in some way. Women are luckier: only about one in two hundred is affected on this matter. Perhaps, after all, it is safer to be driven by a woman!

There are different forms of color-blindness. In some cases a man may not be able to see deep red. He may think that red, orange and yellow are all shades of green. Sometimes a person cannot tell the difference between blue and green. In rare cases an unlucky man may see everything in shades of green — a strange world indeed.

Color-blindness in human beings is a strange thing to explain. In a single eye there are millions of very small things called "cones". These help us to see in bright light and to tell the difference between colors. There are also millions of "rods", but these are used for seeing when it is near dark. They show us shapes but no color.

Some insects have favorite colors. Mosquitoes（蚊子） prefer blue to yellow. A red light will not attract insects, but a blue lamp will. In a similar way human beings also have favorite colors. Yet we are lucky.

With the aid of the cones in our eyes we can see many beautiful colors by day, and with the aid of the rods we can see shapes at night. One day we may even learn more about the invisible colors around us.

   When a mom attended school to help her disabled son, her son and the school thanked her in the sweetest way. It wasn't until after his college years that Marty became disabled after __down stairs. When her son __to get his MBA, Judy O'Connor attended every class with him to help him write and __. Every day, Judy would sit by Marty in class, taking notes to make sure of __specific requests, raising her hand so he could answer questions, and silently writing down his __on test days. "After a little while, we found that working together we could __a great deal, " Marty says.

On graduation day at Chapman University, Judy was dressed in black to mix in with the other __. Little did she know she'd soon be the center of __. When Marty's name was called, his mom helped __him to the front of the stage, ___for a picture with Marty as he received his diploma. Over the loudspeaker, a（n）___was made in a voice ___with happy tears: The university was giving Judy an honorary（荣誉的）MBA. " A lump came to my throat. I was proud of my son and ___to be honored, " says Judy.

The mother and the son had joked that Judy was putting in enough work to earn her own ___. To Marty, there was no question that his mom,a retired elementary school teacher with a business degree, had ___earned her honorary MBA.

Perhaps just as important, Judy gave Marty ___. Life as Marty knew it before the ___may have changed, but he encourages anyone in a ___situation to keep up hope. " Just keep an open mind, ___you can make your diversity your advantage and take challenges as a（n）___for growth in your life," he says.