但如果需要测试多个条件，例如我们假设所有条件都需要为 True 或 False (AND)，或只有一个条件需要为 True 或 False (OR)，或者如果想要检查某个条件是否不 (NOT) 符合你的条件，这时该怎么做呢？这三个函数均可以单独使用，但它们更常见于与 IF 函数成对使用。

Press Ctrl + Alt + Delete to open Task Manager.If you don’t see Task Manager after pressing Ctrl + Alt + Delete, press Ctrl + Shift + Esc to open Task Manager.. If Task Manager flickers along with everything else on the screen, a display driver is probably causing the problem.

The easiest way to get language packs for Windows 8.1 and Windows RT is to download and install them using the Language Control Panel. Download and install additional languages to view menus, dialog boxes, and other user interface items in your preferred language.

In the search box on the taskbar, type device manager, then select Device Manager from the menu.

Check the Xbox services, games, and apps for any service outages.

Info for Windows Insiders. If you’re an Insider and the current preview build isn’t working for you, select Start > Settings > System > Recovery .Next to Go back , select Go back.This won’t remove your personal files, but it’ll remove recently installed apps and drivers, and change settings back to their defaults.

Here's more info on what permissions allow an app to do: Access all your files, peripheral devices, apps, programs, and registry: The app has the ability to read or write to all your files (including documents, pictures, and music) and registry settings, which allows the app to make changes to your computer and settings. It can use any peripheral devices that are either attached or part of ...

To turn off your PC in Windows 10, select the Start button, select the Power button, and then select Shut down.. I'm having trouble opening the Start menu

Press this key. To do this. Command + Shift + B. Show or hide the favorites bar. Command + Shift + C . Open Developer tools. Command + D. Save your current tab as a favorite. Command + Shift + D. Save all open tabs as favorites in a new folder

When prompted, enter the product key. You can find the product key on the sticker on the CD case or other packaging. If you need help, see Find your Product Key for Office 2007.