use some index from end expressions

src/Humanizer/Localisation/NumberToWords/NorwegianBokmalNumberToWordsConverter.cs

@@ -127,7 +127,7 @@ string Convert(int number, bool isOrdinal, GrammaticalGender gender)
             }
             else if (isOrdinal)
             {
-                parts[parts.Count - 1] += (number == 0 ? "" : "en") + (millionOrMore ? "te" : "de");
+                parts[^1] += (number == 0 ? "" : "en") + (millionOrMore ? "te" : "de");
             }
 
             var toWords = string.Concat(parts).Trim();

src/Humanizer/Localisation/NumberToWords/TamilNumberToWordsConverter.cs

@@ -78,7 +78,7 @@ string ConvertImpl(long number, bool isOrdinal)
             if (number > 0)
                 parts.Add(GetTensValue(number, isOrdinal));
             else if (isOrdinal)
-                parts[parts.Count - 1] += "வது";
+                parts[^1] += "வது";
 
             var toWords = string.Join(" ", parts);
 

src/Humanizer/Localisation/NumberToWords/TurkishNumberToWordConverter.cs

@@ -120,7 +120,7 @@ public override string ConvertToOrdinal(int number)
                 }
             }
 
-            if (word[word.Length - 1] == 't')
+            if (word[^1] == 't')
             {
                 word = word.Substring(0, word.Length - 1) + 'd';
             }

src/Humanizer/Localisation/NumberToWords/UzbekCyrlNumberToWordConverter.cs

@@ -85,7 +85,7 @@ public override string ConvertToOrdinal(int number)
                 return string.Empty;
             }
 
-            var lastChar = word[word.Length - 1];
+            var lastChar = word[^1];
             if (lastChar is 'и' or 'а')
             {
                 i = 1;

src/Humanizer/Localisation/NumberToWords/UzbekLatnNumberToWordConverter.cs

@@ -85,7 +85,7 @@ public override string ConvertToOrdinal(int number)
                 return string.Empty;
             }
 
-            var lastChar = word[word.Length - 1];
+            var lastChar = word[^1];
             if (lastChar is 'i' or 'a')
             {
                 i = 1;

src/Humanizer/MetricNumeralExtensions.cs

@@ -98,7 +98,7 @@ static MetricNumeralExtensions()
         public static double FromMetric(this string input)
         {
             input = CleanRepresentation(input);
-            return BuildNumber(input, input[input.Length - 1]);
+            return BuildNumber(input, input[^1]);
         }
 
         /// <summary>