input focus in a sentence

1. This is different from the behaviour of the typical Taskbar and input focus ).
2. It does this by detecting changes in window input focus, based on information on the activities being undertaken on the computer that the program is able to detect.
3. Modal windows are commonly implemented in ways that block the possibility to move, minimize, iconify, or push that window back, and they grab input focus, which often prevents use of a system's cut, copy, and paste facilities.
4. It's difficult to find input focus in a sentence.