Nếu bạn biết câu trả lời, hãy giơ tay lên.
If you know the answer, raise your hand.
Dictionary entry
to raise one's hand
to lift a hand
Examples
Nếu bạn biết câu trả lời, hãy giơ tay lên.
If you know the answer, raise your hand.
Cô giáo yêu cầu học sinh giơ tay nếu muốn phát biểu.
The teacher asked students to raise their hands if they wanted to speak.
Anh ấy giơ tay để xin phép rời phòng họp.
He raised his hand to ask for permission to leave the meeting room.
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