The text box displays the word (prompt text) by default, and the text disappears after clicking.

 

$("#tbContent").val("1. You can add relevant message templates in the message module on the right , After selecting, check the receiver you want to send on the left .\n2. SMS content exceeds 80 Words will be sent in multiple lines !");
            $("#tbContent").bind("click",function(){
               if($("#tbContent").css("color")=="gray"){
                $("#tbContent").css("color","black");
                    $("#tbContent").val("");
    }