Check your keyboard layout and language settings to make sure you are using the appropriate settings for your keyboard.
Go to Settings > Time & Language > Language. In "Preferred languages", select the current language and click Options to access the keyboard settings.
For Windows 7, you can access the settings by opening Control Panel.
If the problem persists or if the settings are set correctly, reboot your laptop; this may solve the keyboard malfunction.
Otherwise, try reinstalling your keyboard driver. Press the Windows + R keys, type devmgmt.msc and press "Enter". Expand the Keyboards section and right-click on your keyboard driver, select Uninstall > Ok and reboot your laptop.