sound、noise、voice的區別：
sound 指各種聲音：
Sound travels slower than light.
聲音比光跑得慢。
Do not make a sound.
別出聲。
noise 主要指「噪音」:
Don't make a noise like a pig.
別學豬叫，那樣吵鬧。
Making noises is annoying.
吵吵嚷嚷很煩人。
voice 指人的「嗓音」:
She has a ringing voice.
她有引領一般的嗓音。
I lost my voice because of a bad cold.
因為重感冒，我嗓子啞了。