假设有一段英文，其中有单独的字母“I”误写为“i”，请编写程

这里给出Python 3.4.2代码，如果使用Python 2.7.8的话只需要修改其中的print()函数为print语句即可。

1）不使用正则表达式

x = "i am a teacher,i am man, and i am 38 years old.I am not a businessman."
x = x.replace('i ','I ')
x = x.replace(' i ',' I ')
print(x)

2）使用正则表达式

x = "i am a teacher,i am man, and i am 38 years old.I am not a businessman."
import re
pattern = re.compile(r'(?:[^\w]|\b)i(?:[^\w])')
while True:
    result = pattern.search(x)
    if result:
        if result.start(0) != 0:
            x = x[:result.start(0)+1]+'I'+x[result.end(0)-1:]
        else:
            x = x[:result.start(0)]+'I'+x[result.end(0)-1:]
    else:
        break
print(x)

	#coding=utf-8
#https://www.nowcoder.com/questionTerminal/931fa0aed84a44d38d7ea792fdfdc12b?orderByHotValue=1&questionTypes=000010&mutiTagIds=573&page=3&onlyReference=false#假设有一段英文，其中有单独的字母“I”误写为“i”，请编写程序进行纠正。
#假设有一段英文，其中有单独的字母“I”误写为“i”，请编写程序进行纠正。 
import re



	x = "i am a teacher,i am man, and i am 38 years old.i am not a businessman."
pattern = re.compile(r'(?:[^\w]|\b)i(?:[^\w])')
while True:
 result = pattern.search(x)
 if result:
  if result.start(0) != 0:
   x = x[:result.start(0)+1]+'I'+x[result.end(0)-1:]
  else:
   x = x[:result.start(0)]+'I'+x[result.end(0)-1:]
 else:
  break
print x