"I learned that e-mail is about as secure as a postcard."
- "I learned that e-mail is about as secure as a postcard."
"I learned that ~" 「〜習った」
"email" 「eメールは」
"is about as secure as ~" 「程度のセキュリテイ」
"a postcard" 「葉書」
I learned that emails have about the same security as a postcard.
「eメールは葉書程度のセキュリテイって習った」は英語で「I learned that emails have about the same security as a postcard.」と言います。「e-mail」と「email」はハイフンなしでも伝わりますし、両方も正しいのでどちらを使っても問題ありません。
私は小学生の頃、eメールは葉書程度のセキュリテイです、だから注意しましょう。
When I was in elementary school, I learned that emails have about the same security as a postcard, so we should be careful.
オーストラリア 
カナダ 
