It may take three days for my friend to receive my letter. Sending a message only takes several seconds. (WHILE) .

It may take three days for my friend to receive my letter while sending a message only takes several seconds.
Giải thích: while: trong khi
Dịch: Nó có lẽ mất 3 ngày để bạn tôi nhận được thư của tôi trong khi gửi 1 tin nhắn chỉ mất vài giây.

It may take three days for my friend to receive my letter. Sending a message only takes several seconds. (WHILE) _____________________________________________________________.

It may take three days for my friend to receive my letter. Sending a message only takes several seconds. (WHILE)
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