diff --git a/htdocs/core/modules/facture/doc/pdf_sponge.modules.php b/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
index bf58ebb6e8e..ae8b33793d2 100644
--- a/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
+++ b/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
@@ -149,7 +149,7 @@ class pdf_sponge extends ModelePDFFactures
 		$this->description = $langs->trans('PDFSpongeDescription');
 		$this->update_main_doc_field = 1;		// Save the name of generated file as the main doc when generating a doc with this template
 
-		// Dimensiont page
+		// Dimension page
 		$this->type = 'pdf';
 		$formatarray=pdf_getFormat();
 		$this->page_largeur = $formatarray['width'];
@@ -423,7 +423,7 @@ class pdf_sponge extends ModelePDFFactures
 	                }
 	            }
 
-	            // Affiche notes
+	            // Display notes
 	            $notetoshow=empty($object->note_public)?'':$object->note_public;
 	            if (! empty($conf->global->MAIN_ADD_SALE_REP_SIGNATURE_IN_NOTE))
 	            {
@@ -462,7 +462,7 @@ class pdf_sponge extends ModelePDFFactures
 	                {
 	                    $pdf->rollbackTransaction(true);
 
-	                    // prepar pages to receive notes
+	                    // prepare pages to receive notes
 	                    while ($pagenb < $pageposafternote) {
 	                        $pdf->AddPage();
 	                        $pagenb++;
@@ -496,7 +496,7 @@ class pdf_sponge extends ModelePDFFactures
 	                    }
 
 
-	                    // apply note frame to previus pages
+	                    // apply note frame to previous pages
 	                    $i = $pageposbeforenote;
 	                    while ($i < $pageposafternote) {
 	                        $pdf->setPage($i);
@@ -557,17 +557,17 @@ class pdf_sponge extends ModelePDFFactures
 	                $height_note=0;
 	            }
 
-	            // Use new auto collum system
+	            // Use new auto column system
 	            $this->prepareArrayColumnField($object, $outputlangs, $hidedetails, $hidedesc, $hideref);
 
-			// Simulation de tableau pour connaitre la hauteur de la ligne de titre
-			$pdf->startTransaction();
-			$this->pdfTabTitles($pdf, $tab_top, $tab_height, $outputlangs, $hidetop);
-			$pdf->rollbackTransaction(true);
+	            // Table simulation to know the height of the title line
+			    $pdf->startTransaction();
+			    $this->pdfTabTitles($pdf, $tab_top, $tab_height, $outputlangs, $hidetop);
+			    $pdf->rollbackTransaction(true);
 
-			$iniY = $tab_top + $this->tabTitleHeight + 2;
-			$curY = $tab_top + $this->tabTitleHeight + 2;
-			$nexY = $tab_top + $this->tabTitleHeight + 2;
+			    $iniY = $tab_top + $this->tabTitleHeight + 2;
+			    $curY = $tab_top + $this->tabTitleHeight + 2;
+			    $nexY = $tab_top + $this->tabTitleHeight + 2;
 
 	            // Loop on each lines
 	            $pageposbeforeprintlines=$pdf->getPage();
@@ -842,19 +842,19 @@ class pdf_sponge extends ModelePDFFactures
 	                $bottomlasttab=$this->page_hauteur - $heightforinfotot - $heightforfreetext - $heightforfooter + 1;
 	            }
 
-	            // Affiche zone infos
+	            // Display infos area
 	            $posy=$this->drawInfoTable($pdf, $object, $bottomlasttab, $outputlangs);
 
-	            // Affiche zone totaux
+	            // Display total zone
 	            $posy=$this->drawTotalTable($pdf, $object, $deja_regle, $bottomlasttab, $outputlangs);
 
-	            // Affiche zone versements
+	            // Display payment area
 	            if (($deja_regle || $amount_credit_notes_included || $amount_deposits_included) && empty($conf->global->INVOICE_NO_PAYMENT_DETAILS))
 	            {
 	                $posy=$this->drawPaymentsTable($pdf, $object, $posy, $outputlangs);
 	            }
 
-	            // Pied de page
+	            // Pagefoot
 	            $this->_pagefoot($pdf, $object, $outputlangs);
 	            if (method_exists($pdf, 'AliasNbPages')) $pdf->AliasNbPages();
 
@@ -1125,7 +1125,7 @@ class pdf_sponge extends ModelePDFFactures
 			// Show payment mode CHQ
 			if (empty($object->mode_reglement_code) || $object->mode_reglement_code == 'CHQ')
 			{
-				// Si mode reglement non force ou si force a CHQ
+			    // If payment mode not forced or forced to CHQ
 				if (! empty($conf->global->FACTURE_CHQ_NUMBER))
 				{
 					$diffsizetitle=(empty($conf->global->PDF_DIFFSIZE_TITLE)?3:$conf->global->PDF_DIFFSIZE_TITLE);
@@ -1213,7 +1213,7 @@ class pdf_sponge extends ModelePDFFactures
 		$tab2_hl = 4;
 		$pdf->SetFont('', '', $default_font_size - 1);
 
-		// Tableau total
+		// Total table
 		$col1x = 120; $col2x = 170;
 		if ($this->page_largeur < 210) // To work with US executive format
 		{
@@ -1226,7 +1226,7 @@ class pdf_sponge extends ModelePDFFactures
 
 
 
-		// pourcentage global d'avancement
+		// overall percentage of advancement
 		$percent = 0;
 		$i=0;
 		foreach ($object->lines as $line)
@@ -1305,7 +1305,7 @@ class pdf_sponge extends ModelePDFFactures
 		        $pdf->setY($posy);
 		    }
 
-		    // Display curent total
+		    // Display current total
 		    $pdf->SetFillColor(255, 255, 255);
 		    $pdf->SetXY($col1x, $posy);
 		    $pdf->MultiCell($col2x-$col1x, $tab2_hl, $outputlangs->transnoentities("PDFSituationTitle", $object->situation_counter).' '.$outputlangs->transnoentities("TotalHT"), 0, 'L', 1);
@@ -1313,7 +1313,7 @@ class pdf_sponge extends ModelePDFFactures
 		    $pdf->SetXY($col2x, $posy);
 		    $facSign = '';
 		    if($i>1){
-		        $facSign = $object->total_ht>=0?'+':''; // gestion d'un cas particulier client
+		        $facSign = $object->total_ht>=0?'+':''; // management of a particular customer case
 		    }
 
 		    if($fac->type === facture::TYPE_CREDIT_NOTE){
diff --git a/htdocs/core/modules/facture/mod_facture_mars.php b/htdocs/core/modules/facture/mod_facture_mars.php
index 3528b4eae3e..3ef5fd0c7ac 100644
--- a/htdocs/core/modules/facture/mod_facture_mars.php
+++ b/htdocs/core/modules/facture/mod_facture_mars.php
@@ -26,7 +26,7 @@
 require_once DOL_DOCUMENT_ROOT .'/core/modules/facture/modules_facture.php';
 
 /**
- * 	Classe du modele de numerotation de reference de facture Mars
+ * 	Class to manage invoice numbering rules Mars
  */
 class mod_facture_mars extends ModeleNumRefFactures
 {
@@ -159,7 +159,7 @@ class mod_facture_mars extends ModeleNumRefFactures
 		elseif ($invoice->type == 3) $prefix=$this->prefixdeposit;
 		else $prefix=$this->prefixinvoice;
 
-		// D'abord on recupere la valeur max
+		// First we get the max value
 		$posindice=8;
 		$sql = "SELECT MAX(CAST(SUBSTRING(ref FROM ".$posindice.") AS SIGNED)) as max";	// This is standard SQL
 		$sql.= " FROM ".MAIN_DB_PREFIX."facture";
diff --git a/htdocs/core/modules/facture/mod_facture_mercure.php b/htdocs/core/modules/facture/mod_facture_mercure.php
index 44efad2ef92..bb8f94d43a1 100644
--- a/htdocs/core/modules/facture/mod_facture_mercure.php
+++ b/htdocs/core/modules/facture/mod_facture_mercure.php
@@ -74,7 +74,7 @@ class mod_facture_mercure extends ModeleNumRefFactures
         $tooltip.=$langs->trans("GenericMaskCodes4a", $langs->transnoentities("Invoice"), $langs->transnoentities("Invoice"));
         $tooltip.=$langs->trans("GenericMaskCodes5");
 
-        // Parametrage du prefix
+        // Setting the prefix
         $texte.= '<tr><td>'.$langs->trans("Mask").' ('.$langs->trans("InvoiceStandard").'):</td>';
         $texte.= '<td class="right">'.$form->textwithpicto('<input type="text" class="flat" size="24" name="maskinvoice" value="'.$conf->global->FACTURE_MERCURE_MASK_INVOICE.'">', $tooltip, 1, 1).'</td>';
 
@@ -82,17 +82,17 @@ class mod_facture_mercure extends ModeleNumRefFactures
 
         $texte.= '</tr>';
 
-        // Parametrage du prefix des replacement
+        // Prefix setting of replacement invoices
         $texte.= '<tr><td>'.$langs->trans("Mask").' ('.$langs->trans("InvoiceReplacement").'):</td>';
         $texte.= '<td class="right">'.$form->textwithpicto('<input type="text" class="flat" size="24" name="maskreplacement" value="'.$conf->global->FACTURE_MERCURE_MASK_REPLACEMENT.'">', $tooltip, 1, 1).'</td>';
         $texte.= '</tr>';
 
-        // Parametrage du prefix des avoirs
+        // Prefix setting of credit note
         $texte.= '<tr><td>'.$langs->trans("Mask").' ('.$langs->trans("InvoiceAvoir").'):</td>';
         $texte.= '<td class="right">'.$form->textwithpicto('<input type="text" class="flat" size="24" name="maskcredit" value="'.$conf->global->FACTURE_MERCURE_MASK_CREDIT.'">', $tooltip, 1, 1).'</td>';
         $texte.= '</tr>';
 
-        // Parametrage du prefix des acomptes
+        // Prefix setting of deposit
         $texte.= '<tr><td>'.$langs->trans("Mask").' ('.$langs->trans("InvoiceDeposit").'):</td>';
         $texte.= '<td class="right">'.$form->textwithpicto('<input type="text" class="flat" size="24" name="maskdeposit" value="'.$conf->global->FACTURE_MERCURE_MASK_DEPOSIT.'">', $tooltip, 1, 1).'</td>';
         $texte.= '</tr>';
diff --git a/htdocs/core/modules/facture/mod_facture_terre.php b/htdocs/core/modules/facture/mod_facture_terre.php
index 0727e4df4e2..d5196867b67 100644
--- a/htdocs/core/modules/facture/mod_facture_terre.php
+++ b/htdocs/core/modules/facture/mod_facture_terre.php
@@ -26,7 +26,7 @@ require_once DOL_DOCUMENT_ROOT .'/core/modules/facture/modules_facture.php';
 
 /**
  *  \class      mod_facture_terre
- *  \brief      Classe du modele de numerotation de reference de facture Terre
+ *  \brief      Class of numbering module Terre for invoices
  */
 class mod_facture_terre extends ModeleNumRefFactures
 {
@@ -189,7 +189,7 @@ class mod_facture_terre extends ModeleNumRefFactures
 		if ($invoice->type == 2) $prefix=$this->prefixcreditnote;
 		elseif ($invoice->type == 3) $prefix=$this->prefixdeposit;
 		else $prefix=$this->prefixinvoice;
-		// D'abord on recupere la valeur max
+		// First we get the max value
 		$posindice=8;
 		$sql = "SELECT MAX(CAST(SUBSTRING(ref FROM ".$posindice.") AS SIGNED)) as max";	// This is standard SQL
 		$sql.= " FROM ".MAIN_DB_PREFIX."facture";
diff --git a/htdocs/core/modules/facture/modules_facture.php b/htdocs/core/modules/facture/modules_facture.php
index a2bd576bdcd..ba65eeeca9c 100644
--- a/htdocs/core/modules/facture/modules_facture.php
+++ b/htdocs/core/modules/facture/modules_facture.php
@@ -23,13 +23,13 @@
 /**
  *	\file       htdocs/core/modules/facture/modules_facture.php
  *	\ingroup    facture
- *	\brief      Fichier contenant la classe mere de generation des factures en PDF
- * 				et la classe mere de numerotation des factures
+ *	\brief      File that contains parent class for invoices models
+ *              and parent class for invoices numbering models
  */
 
 require_once DOL_DOCUMENT_ROOT.'/core/class/commondocgenerator.class.php';
 require_once DOL_DOCUMENT_ROOT.'/product/class/product.class.php';
-require_once DOL_DOCUMENT_ROOT.'/compta/bank/class/account.class.php';   // Requis car utilise dans les classes qui heritent
+require_once DOL_DOCUMENT_ROOT.'/compta/bank/class/account.class.php';   // Required because used in classes that inherit
 
 
 /**
@@ -66,7 +66,7 @@ abstract class ModelePDFFactures extends CommonDocGenerator
 }
 
 /**
- *  Classe mere des modeles de numerotation des references de facture
+ *  Parent class of invoice reference numbering templates
  */
 abstract class ModeleNumRefFactures
 {