A few other grammar changes

Author: cpursley

chapters/dates_and_times/days-between-two-dates.md

@@ -5,11 +5,11 @@ chapter: Dates and Times
 ---
 ## Problem
 
-You need to find how many seconds, minutes, hours, days, months or years has passed between two dates.
+You need to find how many seconds, minutes, hours, days, months or years have passed between two dates.
 
 ## Solution
 
-Use JavaScript's Date function  getTime(). Which provides how much time in milliseconds has passed since 01/01/1970:
+Use JavaScript's Date function  getTime(). Which provides how much time in milliseconds have passed since 01/01/1970:
 
 {% highlight coffeescript %}
 DAY = 1000 * 60 * 60  * 24
@@ -23,9 +23,9 @@ days_passed = Math.round((d2.getTime() - d1.getTime()) / DAY)
 ## Discussion
 
 Using milliseconds makes the life easier to avoid overflow mistakes with Dates. So we first calculate how many milliseconds are in a day.
-Then, given two distinct dates, just get the difference in milliseconds between two dates and then divide by how many milliseconds are in a day. It will return the days between two distinct dates.
+Then, given two distinct dates, get the difference in milliseconds between two dates and then divide by how many milliseconds are in a day. It will return the days between two distinct dates.
 
-If you'd like to calculate the hours between two date objects, you can do that just by dividing the difference in milliseconds by the conversion of milliseconds to hours. The same goes for minutes and seconds.
+If you'd like to calculate the hours between two date objects, you can do that by dividing the difference in milliseconds by the conversion of milliseconds to hours. The same goes for minutes and seconds.
 
 {% highlight coffeescript %}
 HOUR = 1000 * 60 * 60