String.Concat – Concatenates one or more instances of string or string representation of objects. Expression: String.Concat (VarName1, VarName2) Output datatype: String Contains – Checks whether a specified substring occurs within a string and returns either true or false. Expression: VarName.Contains (“text”) Output datatype: Boolean String.Format – Converts the value of objects to strings and inserts them into another string. Expression: String.Format(“{0} is {1}”, VarName1, VarName2) Output datatype: String IndexOf – Returns the index position of the first occurrence of a specified character or a substring. Expression: VarName1.IndexOf(“a”) Output datatype: Int32 LastIndexOf – Returns the index position of the last occurrence of a specified character or a substring. Expression: VarName1.LastIndexOf("author") Output datatype: Int32 String.Join – Concatenates the elements in a collection using the specified separator and displays them as a String. Expression: String.Join(“|”...