Students of second language complain that during the lesson they remember the vocab, while they forget all when they are out, what should they do?

When foreign language students do not live in immersion abroad, or do not have enough exposure to the language they study (from their family, TV or group of friends), they may indeed feel that their learning process is too secluded and limited to the time they spend in the classroom. It is at the same time natural and potentially injurious to their progress.There are several ways of bypassing that issue, and perhaps even turn it into a kind of strength, as long as they are encouraged to keep being involved in learning outside the classroom.What I would call the conservative methods are : giving more homework, ranging from mere rule-application and pattern-using exercises ; to presentations and projects to prepare at home, which will turn their purely linguistic knowledge (necessarily fragile and conditioned by good memory skills) into a more actual, task-based relationship to the language ; and giving regular quizzes and tests in class (be they surprise-quizzes or planned ones) so that learners know they have to repeat and study the course content at home.Vocabulary, besides, cannot be learnt separately from the rest. Give a plain list of words to a student : he/she may well learn it on a short-term basis (for a quiz, for instance), but there's almost no possibility he/she may keep it in mind and activate it in a more synthetic, articulate way.That is why one has to teach vocabulary through action and tasks, linking it as often as possible with actual, everyday situations -which will contextualize and give meaning, sense and relevance to the vocabulary itself, in addition to more concrete motivation to the student. Last but not least, students should learn how to do away with the vocabulary as creatively as possible : everybody, including native speakers, happens to forget the words they had in mind, every now and then. What happens then ? Rephrasing, mimicking, improvising. That is what students should also be able to do. They should learn as much as possible that a language is not only a dry salad of words and rules, but also a whole world of symbols, codes and tricks which, in every given situation, happen to make sense.

There are a number of issues here. Firstly,  I think it is about learning for meaning or rote learning.  With rote learning words and letters are focussed on.  With learning for meaning, the interaction is meaningful.  In other words the learner is able to make sense of what he or she is learning within a context.  I guess the question is being raised in the area of second language or third language acquistion.  At another level there are challenges if the learner is not required to speak the language in daily life and uses another language outside the classroom.  In the final analyses it will depend on how much one wants to learn a language. Of course the teacher is important but the learner, if it is a second or third languague, has to make it meaningful.  Interacting with others outside who speak the language, read books in that language, listen to tapes or watch television programmes.  If the learner restricts learning to the classroom then there is no chance that the learner will arrive a any level of proficiency in the language.

Practice make perfect. To write down the meanings and to use newly learned words in sentences is a good drill to stay smart in vocabulary. Finding synonyms and antonyms of selected words is also a good habit to improve vocabulary.

Hello,

One of the best ways to retain what has been learned is to make additional time and trips to place just for using specific vocabulary words. If you have a class on a visit to the mall. Then take a half hour or more and go to the mall with the mindset of using the newly acquired vocabulary. This an assignment I assigned that bore wonderful results. Or you can make a special alarm on your phone, so when it goes off it is a reminder to start speaking in that second language. And laslty, one of the most effective means is to have a "Second Language Sponsor". You two can work out a schedule where they are to "Call" you at a specific time of the day and speak only in the language you are trying to master. I hope this helps!