diff --git a/README.cn.md b/README.cn.md
index 72d7f1c..85280a8 100644
--- a/README.cn.md
+++ b/README.cn.md
@@ -1571,8 +1571,6 @@ invalid timezone "xxx", please see the file "$GOROOT/lib/time/zoneinfo.zip" for
 | H | 小时，24 小时格式 | 2 | 00-23 | 15 |
 | i | 分钟 | 2 | 01-59 | 04 |
 | s | 秒数 | 2 | 01-59 | 05 |
-| c | ISO8601 格式日期 | - | - | 2006-01-02T15:04:05-07:00 |
-| r | RFC2822 格式日期 | - | - | Mon, 02 Jan 2006 15:04:05 -0700 |
 | O | 与格林威治时间相差的小时数 | - | - | -0700 |
 | P | 与格林威治时间相差的小时数，小时和分钟之间有冒号分隔 | - | - | -07:00 |
 | T | 时区缩写 | - | - | MST |
diff --git a/README.jp.md b/README.jp.md
index 8aec132..1c231e2 100644
--- a/README.jp.md
+++ b/README.jp.md
@@ -1567,8 +1567,6 @@ invalid timezone "xxx", please see the file "$GOROOT/lib/time/zoneinfo.zip" for
 | H | 時間, 24時間のフォーマット | 2 | 00-23 | 15 |
 | i | 分 | 2 | 01-59 | 04 |
 | s | 秒 | 2 | 01-59 | 05 |
-| c | ISO8601 フォーマットの日付 | - | - | 2006-01-02T15:04:05-07:00 |
-| r | RFC2822 フォーマットの日付 | - | - | Mon, 02 Jan 2006 15:04:05 -0700 |
 | O | グリニッジとの時間差の時間数 | - | - | -0700 |
 | P | グリニッジと時間の差の時間数, 時間と分の間にコロンがあります | - | - | -07:00 |
 | T | タイムゾーンの略語 | - | - | MST |
diff --git a/README.md b/README.md
index a3c3bc9..ab54fd4 100644
--- a/README.md
+++ b/README.md
@@ -1571,8 +1571,6 @@ invalid timezone "xxx", please see the file "$GOROOT/lib/time/zoneinfo.zip" for
 |  H   |                                  Hour in 24-hour format, padded to 2                                   |   2    |      00-23       |               15                |
 |  i   |                                          Minute, padded to 2                                           |   2    |      01-59       |               04                |
 |  s   |                                          Second, padded to 2                                           |   2    |      01-59       |               05                |
-|  c   |                                              ISO8601 date                                              |   -    |        -         |    2006-01-02T15:04:05-07:00    |
-|  r   |                                              RFC2822 date                                              |   -    |        -         | Mon, 02 Jan 2006 15:04:05 -0700 |
 |  O   |               Difference to Greenwich time (GMT) without colon between hours and minutes               |   -    |        -         |              -0700              |
 |  P   |                Difference to Greenwich time (GMT) with colon between hours and minutes                 |   -    |        -         |             -07:00              |
 |  T   |                                          Abbreviated timezone                                          |   -    |        -         |               MST               |
diff --git a/helper.go b/helper.go
index c4685d3..be81c47 100755
--- a/helper.go
+++ b/helper.go
@@ -8,28 +8,26 @@ import (
 // common formatting symbols
 // 常规格式化符号
 var formats = map[byte]string{
-	'd': "02",                              // Day:    Day of the month, 2 digits with leading zeros. Eg: 01 to 31.
-	'D': "Mon",                             // Day:    A textual representation of a day, three letters. Eg: Mon through Sun.
-	'j': "2",                               // Day:    Day of the month without leading zeros. Eg: 1 to 31.
-	'l': "Monday",                          // Day:    A full textual representation of the day of the week. Eg: Sunday through Saturday.
-	'F': "January",                         // Month:  A full textual representation of a month, such as January or March. Eg: January through December.
-	'm': "01",                              // Month:  Numeric representation of a month, with leading zeros. Eg: 01 through 12.
-	'M': "Jan",                             // Month:  A short textual representation of a month, three letters. Eg: Jan through Dec.
-	'n': "1",                               // Month:  Numeric representation of a month, without leading zeros. Eg: 1 through 12.
-	'Y': "2006",                            // Year:   A full numeric representation of a year, 4 digits. Eg: 1999 or 2003.
-	'y': "06",                              // Year:   A two digit representation of a year. Eg: 99 or 03.
-	'a': "pm",                              // Time:   Lowercase morning or afternoon sign. Eg: am or pm.
-	'A': "PM",                              // Time:   Uppercase morning or afternoon sign. Eg: AM or PM.
-	'g': "3",                               // Time:   12-hour format of an hour without leading zeros. Eg: 1 through 12.
-	'h': "03",                              // Time:   12-hour format of an hour with leading zeros. Eg: 01 through 12.
-	'H': "15",                              // Time:   24-hour format of an hour with leading zeros. Eg: 00 through 23.
-	'i': "04",                              // Time:   Minutes with leading zeros. Eg: 00 to 59.
-	's': "05",                              // Time:   Seconds with leading zeros. Eg: 00 through 59.
-	'O': "-0700",                           // Zone:   Difference to Greenwich time (GMT) in hours. Eg: +0200.
-	'P': "-07:00",                          // Zone:   Difference to Greenwich time (GMT) with colon between hours and minutes. Eg: +02:00.
-	'T': "MST",                             // Zone:   Timezone abbreviation. Eg: UTC, EST, MDT ...
-	'c': "2006-01-02T15:04:05-07:00",       // Format: ISO 8601 date. Eg: 2004-02-12T15:19:21+00:00.
-	'r': "Thu, 21 Dec 2000 16:01:07 +0200", // Format: RFC 2822 formatted date. Eg: Thu, 21 Dec 2000 16:01:07 +0200.
+	'd': "02",      // Day:    Day of the month, 2 digits with leading zeros. Eg: 01 to 31.
+	'D': "Mon",     // Day:    A textual representation of a day, three letters. Eg: Mon through Sun.
+	'j': "2",       // Day:    Day of the month without leading zeros. Eg: 1 to 31.
+	'l': "Monday",  // Day:    A full textual representation of the day of the week. Eg: Sunday through Saturday.
+	'F': "January", // Month:  A full textual representation of a month, such as January or March. Eg: January through December.
+	'm': "01",      // Month:  Numeric representation of a month, with leading zeros. Eg: 01 through 12.
+	'M': "Jan",     // Month:  A short textual representation of a month, three letters. Eg: Jan through Dec.
+	'n': "1",       // Month:  Numeric representation of a month, without leading zeros. Eg: 1 through 12.
+	'Y': "2006",    // Year:   A full numeric representation of a year, 4 digits. Eg: 1999 or 2003.
+	'y': "06",      // Year:   A two digit representation of a year. Eg: 99 or 03.
+	'a': "pm",      // Time:   Lowercase morning or afternoon sign. Eg: am or pm.
+	'A': "PM",      // Time:   Uppercase morning or afternoon sign. Eg: AM or PM.
+	'g': "3",       // Time:   12-hour format of an hour without leading zeros. Eg: 1 through 12.
+	'h': "03",      // Time:   12-hour format of an hour with leading zeros. Eg: 01 through 12.
+	'H': "15",      // Time:   24-hour format of an hour with leading zeros. Eg: 00 through 23.
+	'i': "04",      // Time:   Minutes with leading zeros. Eg: 00 to 59.
+	's': "05",      // Time:   Seconds with leading zeros. Eg: 00 through 59.
+	'O': "-0700",   // Zone:   Difference to Greenwich time (GMT) in hours. Eg: +0200.
+	'P': "-07:00",  // Zone:   Difference to Greenwich time (GMT) with colon between hours and minutes. Eg: +02:00.
+	'T': "MST",     // Zone:   Timezone abbreviation. Eg: UTC, EST, MDT ...
 
 	'U': "timestamp",      // Timestamp with second. Eg: 1699677240.
 	'V': "timestampMilli", // TimestampMilli with second. Eg: 1596604455666.