21．David Carter stands outside of the University of Texas' Austin campus every day，offering the same warm greeting to students who pass by． "Hello，my friend!"
Carter，now 68，is a beggar who once attended the school from 1972 to 1975．Then，he was involved in a crash and got serious injuries．He then had trouble with substance abuse and faced mental health challenges，leading him to drop out before completing his degree．
"If I could change one thing about my past life，I would have stayed in school，" Carter says．He says he knows an education can change someone's quality of life．
Carter had to beg in the last few years for a simple reason． "I'm always
flat broke，" he said．While most people would walk right by a beggar，Ryan Chandler，a junior at the university，decided to stop and chat with Carter-and he learned a valuable lesson：You can't judge a book by its cover．
"A lot of UT students see them as criminal vagrants（無業(yè)游民，乞丐） or think that they are dangerous or unfriendly，and that idea just isn't true，" says Chandler．
Chandler got to know Carter and saw his potential． "He completed 87 hours of course credits，which is enough for a degree for most people，but he just never finished，" Chandler says．
The student wrote a blog post about his new friend，and luckily，the right people heard about Carter and stepped in to help．The University of Texas readmitted Carter as a student，and a kind person who used to be a student UT offered to pay for Carter's tuition．
"I want to be a student and I want to learn，" Carter said．Since the course requirements have changed，Carter is far from having the amount of credits needed to graduate．But his friend knows he's willing to take up the challenge． "He is capable，he is ready，and he is dedicated to this，" Chandler says．
（1）Why didn't Carter finish his study at UT more than 40 years ago？ （no more than 10 words）
（2）How does Carter feel as a dropout？ （no more than 5 words）
（3）What does the underlined part in the fourth paragraph probably mean？ （no more than 5 words）
（4）What can be inferred about Carter in his study at UT？ （no more than 15 words）
（5）What do you think is the right way to know someone？Please explain． （no more than 25 words）
