diff --git a/php/src/php/time/MutableDateTime.php b/php/src/php/time/MutableDateTime.php
index c7e69a7..1083444 100644
--- a/php/src/php/time/MutableDateTime.php
+++ b/php/src/php/time/MutableDateTime.php
@@ -139,6 +139,9 @@ class MutableDateTime extends \DateTime {
     $this->setTime(0, 0);
     return $this;
   }
+  function getStartOfDay(): self {
+    return $this->clone(true)->setStartOfDay();
+  }
 
   /**
    * modifier cet objet pour que l'heure soit à 23:59:59.999999 ce qui le rend
@@ -148,6 +151,9 @@ class MutableDateTime extends \DateTime {
     $this->setTime(23, 59, 59, 999999);
     return $this;
   }
+  function getEndOfDay(): self {
+    return $this->clone(true)->setEndOfDay();
+  }
 
   function setPrevDay(int $nbDays=1, bool $skipWeekend=false): self {
     if ($nbDays == 1 && $skipWeekend && $this->wday == 1) {
@@ -156,6 +162,9 @@ class MutableDateTime extends \DateTime {
     $this->sub(new \DateInterval("P${nbDays}D"));
     return $this;
   }
+  function getPrevDay(int $nbDays=1, bool $skipWeekend=false): self {
+    return $this->clone(true)->setPrevDay($nbDays, $skipWeekend);
+  }
 
   function setNextDay(int $nbDays=1, bool $skipWeekend=false): self {
     if ($nbDays == 1 && $skipWeekend) {
@@ -165,4 +174,7 @@ class MutableDateTime extends \DateTime {
     $this->add(new \DateInterval("P${nbDays}D"));
     return $this;
   }
+  function getNextDay(int $nbDays=1, bool $skipWeekend=false): self {
+    return $this->clone(true)->setNextDay($nbDays, $skipWeekend);
+  }
 }