c# - Problem creating objects, class could not be found -

in blllanguage.cs class not able create dallanguage class's objects , vice versa. says dallanguage.cs/blllanguage.cs not found. whats wrong code below?

blllanguage.cs

using system; using system.data; using system.configuration; using system.linq; using system.web; using system.collections; using system.web.security; using system.web.ui; using system.web.ui.htmlcontrols; using system.web.ui.webcontrols; using system.web.ui.webcontrols.webparts; using system.xml.linq; using proj2;   namespace proj2.bll.main.setting {     public class blllanguage     {          public blllanguage()         {          //add constructor code here         }          #region properties         /// <summary>         /// properties         /// </summary>         private int intlanguageid;         private string strdescription;         private string strvalue;          #endregion          public int languageid         {             { return intlanguageid; }             set { intlanguageid = value; }         }         public string description         {             { return strdescription; }             set { strdescription = value; }         }         public string value         {             { return strvalue; }             set { strvalue = value; }         }          #region getlanguage         /// <summary>         /// getlanguage         /// </summary>         /// <returns></returns>         public dataset getlanguage()         {               dallanguage objdallanguage = new dallanguage(); // error here             dataset dsgetlanguage = objdallanguage.getlanguage();             return dsgetlanguage;          }         #endregion         } } 

dallanguage.cs

using system; using system.data; using system.configuration; using system.linq; using system.data.sqlclient; using system.web; using microsoft.applicationblocks.data; using system.web.security; using system.web.ui; using system.web.ui.htmlcontrols; using system.web.ui.webcontrols; using system.web.ui.webcontrols.webparts; using system.xml.linq; using proj2;  namespace proj2.dal.main.setting {    public class dallanguage     {         public dallanguage()         {          //constructor code here         }           #region getlanguage         /// <summary>         /// getlanguage         /// </summary>         /// <returns></returns>         public dataset getlanguage()         {             dataset dsgetlanguage = new dataset();             try             {                  dsgetlanguage = sqlhelper.executedataset(constants.connectionstring, commandtype.storedprocedure, "[main].[sp_getlanguage]");             }              catch (exception ex)             {                 throw ex;             }             return dsgetlanguage;         }         #endregion        } } 

the namespaces not match

proj2.bll.main.setting proj2.dal.main.setting 

you need specify qualified name or import namespaces. importing proj2 not enough