【摘要】How can we avoid forgetting what we have learned? Now I would like to give you four suggestions. Then I'll give you a bit explanation on each of them.
First, we need to learn words repeatedly with increasing intervals between learning sessions. （按照适当的时间间隔来温习新学的单词。）
The second we should have the words. We have the words we want to learn with us whenever we go. So if we want to learn these words, we should have these words with us. So we can make full use of our time learning these words. （时时刻刻，利用边边角角的时间去复习生词。）
The third is set aside a regular time for vocabulary learning. （留出专门的时间用于单词学习。）
The last one, spend more time on the words you find difficult. All these suggestions are not new to you, I guess. But you might find something new later. （对疑难词汇进行重点攻关。）
【Suggestion One 】Increasing intervals.
Now research in psychology shows that we do not forget things gradually. You see a psychologist did research. Most of our forgetting occurs within 20 minutes after we have first learned something. More is forgotten with one hour. Still more within 8 hours. After 8 hours, the rate of forgetting stays surprisingly steady. You see, we do not forget things gradually, bit by bit. Bit by bit. It’s not the case. So we forget more in the first 8 hours. （心理学研究者做过一个测试：我们最易遗忘的时间段是我们接触新知识后的头20分钟。之后的1个小时我们又会忘记一些，然后8小时内又忘记一些。过了8小时，我们的遗忘速度就会趋于稳定。也就是说，遗忘是一点一点发生的，前8个小时忘得最快。）
So what should we do? What should we do? And actually, I will suggest you should do revision everyday when you first learn the new words. And then you may spend some time review the words once in a week. Then later on, once in a month. So increasing intervals, I mean you learn frequently at the very beginning. Then gradually, you can delay a little bit. The interval is longer and longer. But still you have to review them.（接触新单词之后，起初反复记忆，然后逐步拉长复习的时间间隔。）
【Suggestion Two】The “Dead” Time.
Now when I say “dead” time, I mean those time is not useful any more. You know, when you are walking on the way, when you are in a bus, when you are, let me see, when you are lying on the bed before you sleep. All these time can’t be used for very important things. But you can make full use of “dead” time to learn some words. And you can use your vocabulary notebook, you can use your electronic dictionary, just very small, learn few words every day. Every day. Try to use this kind of time learning words, eventually your vocabulary will be expanding quickly. （利用一切可以利用的时间。行走中，公车上，睡觉前......这些相对来说不能做重要事情的时间段，你就可以分心用来背单词。一天记几个，积少成多，你就会发现自己的单词量突飞猛进。）
You do not need whole day learning vocabulary. Don’t do in this way. And you may use just small amount of time every day. Let’s say, in the morning, 20 minutes, in the afternoon, 20 minutes, in the evening, 20 minutes. Suppose you want to spend one hour, you’d better separate it into three sessions, 20 minutes each. Suppose you want to learn vocabulary half an hour a day, maybe you’d better divide them into two sections, 15 minutes a section. Don’t put them together. （不要成天成宿地背单词，花费大段大段的时间记单词会降低学习效率。如果你每天计划利用1个小时背单词，那么就把这1个小时拆分成早、中、晚三部分，每次安排20分钟背单词。）
And then every day you learn a little bit. Then eventually, at the end of the week, you have spent about half an hour putting all these words together, go over them. Later I will mention, don’t go over all the words. You have to select some of them to focus your attention. Now electronic dictionary also is a good way to learn words, because there is a sort of file for you to put those difficult words, right? Just put in your pocket. You can learn them anytime you can do it. （一天记一点，周末抽出半小时有侧重点地巩固一周的学习成果。可以利用电子辞典的归档功能筛选出疑难词汇，然后放在身边随时翻阅。）