reporting services - SSRS IIF statements expressions for conditional date formatting (BETWEEN) -

I want to make a conditional format on date ranges. Therefore, if the date is set to start / end range (parameter @biggin and @End ) between 5 to 7 days, display "week" if "month" display , everything else, show "X days" between <28> and 31 days e.t.c.

I have something like this, but it is not calculated by way of sentence. I am struggling with this one so that someone can help me in the right direction or can I point out?

Example me;

  = datein value = today () and parameter! Date: Value = Today (), "Today", IIF (Parameter! Datebeam Value = Date Add ("D", - 1, today ()) and parameter! Date.value = today (), "tomorrow", IIF (parameter! Datebee value and parameter date. Date * difference between 5-7 days * , "Week", IIF (Parameters! Datebeen Value and Parameter Date Date Value * Difference Between 28-31 days *, "Month", Rest Everything * = * Between the parameters * Date and Time Date and Value Date. 
 
 
 It looks like you have  DATEDIFF ()  function. 
 
 For example (5 -7 days): 
 
  Iif ((ditf ("d", parameter! Dated bin value, parameter! Dateind.value)> 4) AND (datediff ("D", parameter ! DateBean Price, Date of Date Date.), 8), "Week", [etc.] ]