1.where引导定语从句时，其先行词一般是表示地点的名词，它在定语从句中作地点状语，此时where相当于at/in/on+which。如：
This is the house where I lived two years ago.
这就是我两年前住的房子。
在这里，where前面有表示地点的先行词house，所以where引导的是定语从句，此时where是关系副词。再看：
Is there a shop around where/in which I can blow my bike tyres up?
附近有什么店可以让我给我的自行车车胎打气吗？
I found my books where I had left them.
我在我放书的地方找到了书。
在上句中，where前面没有表示地点的先行词，books不是表示地点，所以where引导的是状语从句，此时where是从属连词。
We should go where we are needed.我们应该到需要我们的地方去。
Where there is a will, there is a way.有志者，事竟成。
2.近年高考试题中对于where的考查趋于复杂化，由明显的地点转为模糊的或抽象的地点。当先行词是case, point, stage, situation, position, career, business, activity，point，condition ，job，race，experiment等表示某人、某物的情况、某事发展的阶段、某事的某个方面的名词，且定语从句中缺少状语时，常用where引导。
There comes a point where you give up.
现在你该放弃了。
It got to the point where I was so ill I was waiting to die.
病到这个程度，我只能等死了。
The Chinese nation has reached a point where its very existence is at stake.
中华民族到了这生死存亡的关头。
You reach a point where medicine can’t help.你已经不可救药。
Then I got to the point where I was staying up really late at night to get my work done ．
然后我就到了晚上熬夜完成工作的地步。
高考真题- 2018 浙江
After graduation she reached a point in her career where she needed to decide what to do.
毕业后，她在事业上达到了需要决定做什么的地步。
We are trying to reach a point where both sides will sit down together and talk.
我们正在努力达成一个共识，双方将坐在一起进行谈判。
It was yet another case where the human eye outperformed radar.
这是肉眼胜过雷达的又一事例。
There are cases where the word “mighty” is used as an adverb.
有些情况下，单词“mighty”用作副词。
I got to the stage where I wasn't coping any more.
到了这个阶段，我已经无法应付了。
The process of political change in South Africa has reached the stage where it is irreversible
南非的政治变革已达到不可逆转的地步。
She’s got herself into a dangerous situation where she’s likely to lose her life.
她将自己置于了危险的境地，而且很有可能丢掉性命。
He's got himself into a dangerous situation where he is likely to lose control over the plane .(高考真题)
他陷入了危险境地，很可能会失去对飞机的控制。
If you risk something important ,you cause it to be in a dangerous situation where might lose it.
你如果拿重要的东西去冒险，那你就是将它置于一种可能会失去它的危险境地。
He got into a situation where it is hard to decide what is right and wrong.
他陷入了一种很难判断什么是对什么是错的情况。
It’s helpful to put children in a situation where they can see themselves differently.
把孩子们置于一种他们能以不同的方式看待自己的环境中是很有帮助的。
He was in a position where he had to force a decision.
他当时的处境是，不得不强行推动作出决定。
It’s put me in a position where I can’t afford to take the job.
我陷入了一种不能接受此项工作的境地。
Sales director is a position where communication ability is just as important as sales skills.
销售主管是一个既要求交际能力，又要求销售能力的职位。（高考真题）
He has talked himself into a position where he will have no option but to go.
他通过耍嘴皮子得到了一个职位，现在他只能硬着头皮去了。
Those successful deaf dancers think dancing is an activity where sight matters more than hearing.
那些成功的聋人舞者认为跳舞是一项让人看比听更重要的活动。
You could look for a career abroad where environmental jobs are better paid and more secure
你可以在国外找一份工作，那里与环境相关的工作报酬更高，也更稳定。
He was in a job where he felt unappreciated and undervalued.
他以前的工作未让他感到受赏识和重视。
She wants a job where her management skills can be put to good use.
她想找一份能充分发挥管理技能的工作。
I don’t want a job where I’m chained to a desk all day.
我不想找一份整天坐在办公桌前的工作。
He wrote a letter where he explained what had happened in the accident.
他写了一封信，在信中他解释了事故中发生的一切。（高考真题）
Life is a long race where we compete with others to go beyond ourselves.
人生是一场漫长的比赛，我们与他人竞争，超越自我。
In experiments where young teens are allowed to sleep as long as they want, they tend to sleep an average of 9 hours.
经验告诉我们，青少年可以想睡多久就睡多久，他们倾向于平均睡9个小时。
注意，where引导同位语从句有时候和定语从句也很像：
They haven't yet settled the question where we are going to spend our summer vacation.到哪儿去度假，这个问题他们还没有决定。
I have no idea where we should go for a holiday. 我不知道我们该去哪里度假。