Step as below
1.open Spotlight, click the magnifying glass icon in the upper-right corner of the menu bar,
2.Type boot camp assistant and then enter
3.Click Continue
4.Tick the checkbox at “Remove Windows7 or later version”
5.Click continue
6.Click Restore
7.Fill in your MacBook password
8.Click OK
9.Wait until process finish
10.Click Quit
11.(This step to check your window partition already removed).Click At Apple Icon
12.Click at About This Mac
13.You will have only 1 partition and got more capacity on your hard drive.
