Advanced exercises
Enter a regexp that matches words per the instructions. Example of words which should be matched are given below the instructions. The answer is accepted only if all example words are matched, but at the same time words not belonging to the group are not. For example, the asnwer .* in the first exercise will not be accepted, because while it does match all 5-character words, it also matches words containing 2 characters or 10 characters.


Exercise 1

Match possessive nouns both in singular and plural.

Find
student's
students'
sister's
countries'
WELL DONE!
INCOMPLETE SOLUTION


Exercise 2

Match possessive nouns created from proper nouns, i.e. starting with a capital letter.

Find
John's
Hanna's
Dicken's
Edward's
WELL DONE!
INCOMPLETE SOLUTION


Exercise 3

Match words containing the string 'blah' at least twice.

Find
blahblah
blahblahblah
WELL DONE!
INCOMPLETE SOLUTION


Exercise 4

Match URLs from the .org domain.

Find
https://www.myblog345.org
http://www.thiISbeautiful.org
https://www.beauty&fashion.org
WELL DONE!
INCOMPLETE SOLUTION


Exercise 5

Match phone numbers starting with the country code +420.

Find
+420 437 175 706
+420 284 266 499
+420 773 230 265
WELL DONE!
INCOMPLETE SOLUTION


Exercise 6

Match words starting with a number.

Find
3rd
3D
18th
1st
WELL DONE!
INCOMPLETE SOLUTION


Exercise 7

Match words starting with co- such as the following:

Find
co-founder
coworker
co-author
co-ordinator
co-investigator
WELL DONE!
INCOMPLETE SOLUTION


Exercise 8

Match words describing ideology/system starting with anti-.

Find
anti-racism
anti-terrorism
anti-capitalism
WELL DONE!
INCOMPLETE SOLUTION


Exercise 9

Match words consisting of the same letter repeating exactly 3 times.

Find
AAA
www
xxx
WELL DONE!
INCOMPLETE SOLUTION


Exercise 10

Match words containing three characters, where the first and last character are the same.

Find
eye
mom
pop
did
WELL DONE!
INCOMPLETE SOLUTION