1. I smoked with concentration and pleasure as I was sure that this would be my last cigarette.
    我聚精会神而又愉快地吸着这枝烟。因为我确信这是我最后一枝烟了。

2. I´d like a cigarette, too.
    我还想抽枝烟。

3. Forest fires are often caused by broken glass or by cigarette ends which people carelessly throw away.
    森林火灾时常由破碎的玻璃或人们随手扔掉的香烟头引起。