What makes people fall in love? This question is even tackled in movies: "But why doesn't he loveme?" sobbed Sally as she mopped up her tears and runny nose inWhen Harry Met Sally. She was heartbroken that her old boyfriend married someone else. Sally is not alone: most old and young lovers experience broken hearts and feelings of rejection in their lives. What makes people fall in love - the chemistry in romantic relationships - can seem like a mystery.

Knowing why we fall in love may help ease feelings of rejection and heartbreak. If someone doesn't fall in love with you, it's not because you're ugly, stupid or poor. Sometimes the chemistry just isn't right. Why we fall in love has been researched extensively.

What Makes People Fall in Love

Psychologist Mark Kristal from the University of Buffalo explains the chemistry in romantic relationships. "There are several types of chemistry required in romantic relationships," he says. "It seems like a variety of different neurochemical processes and external stimuli have to click in the right complex and right sequence for someone to fall in love." The chemistry in romance requires certain elements of love.

1. Smell.We fall in love partly because of smell. The scent of a bouquet of red roses, for instance, is a cultural preference that boosts the chemistry in romantic relationships. Dr Kristal says, "For example, smelling like a strawberry instead of mildew [makes you attractive]." Smelling delicious could be part of why we fall in love.

2. Love pheromones.Invisible signals are part of what makes people fall in love. "Pheromones are unlearned, and perhaps unsmellable, signals that enter the brain through the olfactory system. They can function in sex, alarm, territoriality, aggression, and fear," says Dr Kristal. He believes that we choose specific mates not solely due to pheromones, but for other reasons. Other sensory cues are better explanations for why we fall in love, such as touch, smell, and hearing.

3. The brain.We fall in love partly because of hormones. Oxytocin and vasopressin are present when people fall in love and stay together for a long time. Dopamine is also part of the chemistry in romantic relationships. So, when you're wondering "Why doesn't he love me?" you may have to look to brain chemistry as the answer.

Can you make someone love you? Well, since the chemistry in romantic relationships is affected by smell, you could try approaching someone you like with a dozen roses or a mug of hot chocolate. And since the hormone oxytocin can be created by positive experiences, it might be smart to ensure all your interactions are pleasant ones.

Just remember that the chemistry in romantic relationships doesn't change who you are as a person. Sally inWhen Harry Met Sallywas just as beautiful, smart and funny after her ex-boyfriend married someone else.

两人相爱后快乐地在一起生活并不是神话。澳大利亚研究人员发现了维系一段感情需要什么，它要的不仅仅是爱。

一对夫妇的年龄，以前的婚姻状况，甚至他们是否吸烟，都是影响他们婚姻能否持久的关键，根据澳大利亚国立大学研究人员的研究成果。

这个研究课题叫"什么样的爱才能满足一段婚姻",追踪了2500名夫妇---结婚或同居---从2001到2007,通过比较一直生活在一起的伴侣和离异，或者分手的伴侣两者之间的联系来找出原因。

它发现比妻子大9岁，或大于9岁的丈夫离婚的可能性是男的25岁前就结婚的2倍。

孩子同样也影响到一段婚姻的持久性或两人亲密程度，在结婚前就有孩子的夫妇---无论来自以前一段婚姻或者同一段婚姻---离婚的有20%,而结婚前没有孩子的夫妇只有9%.

女方比男的更急着要孩子离婚的可能性也大为增加。

夫妇双方的父母在他们婚姻关系中也有影响，研究表明父母曾经离异的夫妇双方有16%离婚，而父母不曾离婚的只有10%.

同样，是第二或第三次婚姻的配偶比第一次婚姻的配偶，离婚的可能性高90%.

不足为奇的是，金钱同样对婚姻有影响，婚姻案中的被告指出他们很穷，或者在丈夫---不是妻子，被解雇的地方说他们要离婚的有16%,而有良好财务状况的夫妇只有9%.

而夫妇只有一方吸烟的也更为可能以失败的婚姻告终。

结婚夫妇拥有孩子的多少和年龄，妻子就业率，夫妇工作的时间，这些因素对离婚的风险不会有太大的影响。

这个研究成果是由来自澳大利亚国立大学的乐思·其朋博士，和来自家庭、住房、社区服务和土着事务部门的彭语博士共同着述的。