如果它是锁着的，证明网站是安全的，未锁的情况下，你就不能泄露自己的信用卡号码。

If it is locked, the site is secure, unlocked means that you should not give a credit card number.

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提防不认识的网站或电子邮件地址，永远留神浏览器底下的安全图标(一把锁上的锁或完整的钥匙符号)。

Be wary of websites or email addresses that you don't recognise and always look out for the security icon (a locked padlock or unbroken key symbol) in the bottom of your browser window.

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