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functions-and-operators/string-functions.md

@@ -47,10 +47,10 @@ TiDB supports most of the [string functions](https://dev.mysql.com/doc/refman/5.
 | [`POSITION()`](https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_position)                                               | Synonym for `LOCATE()`                                                                                                                    |
 | [`QUOTE()`](https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_quote)                                                     | Escape the argument for use in an SQL statement                                                                                           |
 | [`REGEXP`](https://dev.mysql.com/doc/refman/5.7/en/regexp.html#operator_regexp)                                                               | Pattern matching using regular expressions                                                                                                |
-| [`REGEXP_INSTR()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-instr) | Return the starting index of substring matching regular expression (partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
-| [`REGEXP_LIKE()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-like) | Whether string matches regular expression (partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
-| [`REGEXP_REPLACE()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-replace) | Replace substrings matching regular expression (partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
-| [`REGEXP_SUBSTR()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-substr) | Return substring matching regular expression (partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
+| [`REGEXP_INSTR()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-instr) | Return the starting index of the substring that matches the regular expression (Partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
+| [`REGEXP_LIKE()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-like) | Whether the string matches the regular expression (Partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
+| [`REGEXP_REPLACE()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-replace) | Replace substrings that match the regular expression (Partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
+| [`REGEXP_SUBSTR()`](https://dev.mysql.com/doc/refman/8.0/en/regexp.html#function_regexp-substr) | Return the substring that matches the regular expression (Partly compatible with MySQL. For more details, see [Regular expression compatibility with MySQL](#regular-expression-compatibility-with-mysql)) |
 | [`REPEAT()`](https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_repeat)                                                   | Repeat a string the specified number of times                                                                                             |
 | [`REPLACE()`](https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_replace)                                                 | Replace occurrences of a specified string                                                                                                 |
 | [`REVERSE()`](https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_reverse)                                                 | Reverse the characters in a string                                                                                                        |
@@ -84,14 +84,14 @@ The following sections describe the regular expression compatibility with MySQL.
 
 ### Syntax compatibility
 
-MySQL implements regular expression using International Components for Unicode (ICU) but TiDB uses RE2. To learn the syntax differences between the two libraries, you can refer to the [ICU documentation](https://unicode-org.github.io/icu/userguide/) and [RE2 Syntax](https://github.com/google/re2/wiki/Syntax).
+MySQL implements regular expression using International Components for Unicode (ICU), and TiDB uses RE2. To learn the syntax differences between the two libraries, you can refer to the [ICU documentation](https://unicode-org.github.io/icu/userguide/) and [RE2 Syntax](https://github.com/google/re2/wiki/Syntax).
 
 ### `match_type` compatibility
 
 The value options of `match_type` between TiDB and MySQL are:
 
 - Value options in TiDB are `"c"`, `"i"`, `"m"`, and `"s"`, and value options in MySQL are `"c"`, `"i"`, `"m"`, `"n"`, and `"u"`.
-- The `"s"` is corresponding to `"n"` in MySQL. When `"s"` is set in TiDB, `.` character matches line terminators in addition.
+- The `"s"` in TiDB corresponds to `"n"` in MySQL. When `"s"` is set in TiDB, the `.` character also matches line terminators (`\n`).
 
     For example, the `SELECT REGEXP_LIKE(a, b, "n") FROM t1` in MySQL is the same as the `SELECT REGEXP_LIKE(a, b, "s") FROM t1` in TiDB.