The key to identifying whether a boy is flirting with you is to notice differences between the way he talks to you and the way he talks to other people.  Some boys try to make their voices sound deeper and more manly when talking to a crush. Sometimes boys will whisper or speak very quietly with someone they're interested in.  This may make you get closer to hear him, or it can sent the signal that you have a secret bond. If he seems overly interested in everything that you do or say, he is probably interested in you, not your interests per se.  Few people have exactly the same hobbies and passions, but everyone looks for commonality when starting a potential new relationship. Be sure that you reciprocate and ask him about his interests as well.  Showing enthusiasm for things that he likes will send the signal that you are also interested.  It will also make you seem less self-involved if you encourage him to share as well. If he knows that he is going to see you, he may pay special attention to preparing his appearance.  Notice if he seems to be dressed up or if he has styled his hair more carefully than usual.  It would be nice to compliment him on his appearance if he appears to have put forth a little extra effort. A boy who is willing to make himself look nice for you is probably a better potential boyfriend than one who seems unwilling to make effort to impress you. Things like cheesy pick-up lines or winking are traditional signs of obvious flirtation, and guys who don't have any other ideas about how to flirt will default to these.

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Write a summary of the previous text in Vietnamese:
So sánh giọng điệu và phong thái của chàng khi gặp riêng bạn và những người khác. Đánh giá sự hào hứng của chàng đối với những mối quan tâm của bạn. Để ý trang phục và thói quen chăm chút bản thân. Chú ý hành động tán tỉnh.