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1. Unless you are careful, you will cut yourself with that knife.

2. Unless you like this one, I'll bring you another.

3. Unless I have a quiet room, I'll not be able to do any work.

4. Unless she hurries, she'll be late.

$#NOCOPY$

1, Unless you careful, you will cut yourself with that knife.

2, Unless you like this one, I will bring you another.

3, I won't be able to do any work unless I have a quiet room.

4, Unless she hurries, she will be late.

 Giải thích: Cấu trúc unless có nghĩa tương đương với If not, vì vậy trong câu điều kiện, cả 2 từ này có thể thay thế cho nhau. Vậy nên ta dùng unless trong câu khẳng định.