| Any character | * | “c”*“t” – allows such words as cat, cot, etc. |
| Letter | C | C”ot” – allows such words as Rot, pot, cot, Dot, mot, etc. |
| Uppercase letter | A | A”ot” – allows such words as Rot, Cot, Mot, Dot, etc. |
| Lowercase letter | a | a”ot” – allows such words as rot, cot, mot, dot, etc. |
| Letter or number | X | X – allows any standalone number or letter. |
| Number | N | N”th” allows such words as 5th, 4th, 6th, etc. |
| String | ” " | "cot” |
| Or | | | “pl”(“o”|“a”)“t” – allows words “plot” and “plat”. |
| Character from group | [] | [tm]“ot” – allows words “tot” and “mot”. |
| Character not from group | [^] | [^t]“ot” – allows words “cot”, “lot”, etc., but does not allow the word “tot”. |
| Space (within group) | \s | [A\s] allows only the letter A or a space. |
Any number of repetitions
(applies to the expression or subexpression on the left) | {-} | [AB74]{-} – allows any combinations of characters A, B, 7, 4 of any length. |
| Number of repetitions n | {n} | N{2}“th” allows such words as 25th, 84th, 11th, etc. |
| From n to m repetitions | {n-m} | N{1-3}“th” allows such words as 5th, 84th, 111th, etc. |
| From 0 to n repetitions | {-n} | N{-2}“th” allows such words as 84th, 5th, etc. |
| From n repetitions and more | {n-} | N{2-}“th” allows such words as 25th, 834th, 311th, 34576th, etc. |
| Subexpression | () | |
| Hyphen symbol | [\-] | |
| Slash symbol | [\\] | |
