re = /\b(?!Zns?\b)[a-zA-Z]+\.\s/m
str = '1) aaa. Zn. bbb
2) aaa. Zn. bbb.
3) aaa Zn. bbb. =
4) aaa Zn. bbb
5) aaa Bns. bbb
6) aaa Bns. Bbb
7) aaa Zn. Aaa Bns. Bbb
8) 1
9) aaa
10) aaa.
11) aaa Abbb
12) aaa. Zns. bbb
13) aaa. Zns. bbb.
14) aaa Zns. bbb.
15) aaa Zns. bbb '
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html