             }
         }
         
+// MARK: - End of time units
         describe("Calculating the end of time units") {
             var dateFormatter : NSDateFormatter!
             beforeEach {
                 dateFormatter = NSDateFormatter()
                 dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
             }
-            
+// MARK: End of hour
             it ("can calculate the end of an hour for date at the end of the hour") {
                 let endOf5PM = dateFormatter.dateFromString("2015-09-08 17:59:59")!
                 expect(TimeUnit().endOfHour(endOf5PM)).to(equal(endOf5PM))

                expect(TimeUnit.hoursOfDay(dateInSeptember5_2015)).to(equal(hoursInSeptember5_2015))
            }
            
            
// MARK: daysOfMonth
            it ("can create days of February 2015") {

                expect(TimeUnit.beginningOfHour(randomTimeIn7AM)).to(equal(beginningOf7AM))
            }
            
// MARK: Beginning of day
            it ("can calculate the beginning of a day for date at the beginning of the day") {
                let beginningOfSeptember8_2015 = dateFormatter.dateFromString("2015-09-08 00:00:00")!
                expect(TimeUnit().beginningOfDay(beginningOfSeptember8_2015)).to(equal(beginningOfSeptember8_2015))
