If you have 2-step verification turned on, Google will send a passcode to your mobile phone when someone tries to sign into your account from an unfamiliar computer.
Kama umewasha uthibitishaji wa hatua mbili, Google itatuma nambari ya siri kwenye simu yako ya mkononi mtu atakapojaribu kuingia katika akaunti yako kutoka kompyuta isiyofahamika.