怎么用正规表达式查找不以某些字符结尾的单词

import re

txt = '''
Dementia is a loss of intellectual ability that affects memory, learning,
attention, thinking and language skills. People with dementia may forget
family members or not know what day it is. Sometimes they become angry or sad,
hear voices, or see things that are not there.

The team found that dementia was the largest cause of disability in the elderly
in areas other than rural India and Venezuela. Other major causes were stroke,
loss of use of arms or legs, arthritis, depression, eyesight problems and
gastrointestinal problems.

The study says the elderly are nine percent of the total population of low and
middle income countries today. But their numbers are growing quickly. They are
expected to reach twenty percent of the total population by the middle of the
century.

It found that in almost half the countries, children who were not breastfeed
were much more likely to have a disability than those who were. The same was
true of those who did not receive vitamin A supplements and those who were
underweight.

Children who did not take part in early learning activities or attend school
were also more likely to be disabled than those who did.
'''

regEndWith_ly = re.compile(r'[a-zA-Z]+?ly', re.I | re.S)
print regEndWith_ly.findall(txt)
regNotEndWith_ly = re.compile(r'\b[a-zA-Z]+?(?<!ly)\b', re.I | re.S)
print regNotEndWith_ly.findall(txt)