Quantifiers apply to the thing in front of them

r'ax*a'      # aa, axa, axxa, axxxa, ...
r'ax+a'      #     axa, axxa, axxxa, ...
r'ax?a'      # aa, axa
r'ax{2,4}a'  #          axxa, axxxa, axxxxa
r'ax{3,}a'   #                axxxa, axxxxa, ...
r'ax{17}a'   #                                 axxxxxxxxxxxxxxxxxa

* 0-
+ 1-
? 0-1
{n,m} n-m
{n,} n-
{n} n