Traditional language instruction in the U. S.
In public schools in the United States, students often enroll in language classes for several years in a row, building their vocabulary and grammatical knowledge of the language they have chosen to study. Unfortunately, these classes are often large and do not accommodate much speaking practice, giving way instead to lectures, readings, and written exercises that cover items designated by the school's curriculum requirements. Even when classes do include significant opportunities to speak, they rarely provide an immersion setting, except at the highest levels.
Language classes and higher education
In college and university language classes, it is more common for classroom time to be immersive, with all instructions and communication taking place in the target language. However, the majority of scheduling structures at the college level only allow for 3 to 5 hours of class time per week. Sometimes, an extra hour or two may be added in the form of language labs devoted to speaking practice. This can help students eliminate mistakes in spoken language, but still is not enough to constitute appropriately immersive language instruction.
One of the best arguments in favor of language immersion is that, when individuals learn their native language, they learn it very quickly through complete immersion. As we age, the language centers in our brain becomes less flexible than it was when we were small children, and learning an additional language with fluency will always take vastly longer than it did to learn the native language. However, complete immersion can help individuals learn languages at a much faster pace than high school and university classes.
Practice, practice, practice
The typical structure of language classes in the United States focuses on one grammatical point or vocabulary topic at a time. For example, students in a Spanish class may spend a few weeks learning vocabulary related to travel and a common form of past tense. When the unit is finished, the class will probably move on to another topic altogether, only revisiting previously covered topics during brief review sessions and on final exams. Although this structure is, to some extent, mandated by the linear nature of schooling, it lacks elements that are crucial to language learning―repetition and practice.
Real versus simulated scenarios
In order to firmly grasp grammar and vocabulary in a foreign language, and retain it in long-term memory, it is important to be repeatedly exposed to these language points and to practice them daily. In an immersion setting, such as studying in a country where the target language is the primary language, practice and repetition occur constantly in naturally occurring daily settings. Compared to, for example, simulating a trip to the grocery store with another student, a language learner could benefit much more from making regular trips to an actual grocery store and having to use the appropriate language to complete the errand. Whereas, students in traditional classes will not be likely to repeat the grocery store scenario more than two or three times, and are thus likely forget the appropriate words and phrases. Going to a real grocery store every few days will help make linguistic knowledge permanent.
Another important element is developing active listening skills. In school classes, students may be required to listen to the instructor, to fellow students, and to media such as TV shows or movies, in order to improve their listening skill. However, there is considerably more room for error in these settings than there is in communicating with native speakers in real situations. For example, a fellow French student probably has not mastered the pronunciation and speaking speed that language learners would encounter among native speakers of French. Thus, the fellow student is easier to listen to and will be more forgiving of a halting response. These conditions could encourage students to develop bad habits and remain at a low level of fluency, which will not serve them well if they ever find themselves in a French-speaking area. Interacting with native speakers of the target language, however, is more likely to trigger a 'trial by fire' or 'fight or flight' mechanism, through which the language learner will be able to process and learn more rapidly than in artificial practice settings.
Alternatives to immersion in foreign countries
Not all people have the ability to immerse themselves in a foreign language by visiting or living in a country where it is spoken. This should not discourage serious language students from seeking out immersion settings, however. Immersion-style courses are offered by private language schools in most areas, and many cities and towns have language groups that meet regularly to practice their target language. Additionally, those with a good grasp of English (or their own native language) could arrange a language lesson swap with a native speaker of their target language. For example, a native English speaker could meet regularly with a native Japanese speaker to practice and trade lessons in the two languages.
No matter how immersion is achieved, it remains a crucial element to the successful development of foreign language skills, without which, many students acquire only 'academic' language skills. They may be able to read and write in their target language, and they may have a firm grasp of grammatical rules, but when it comes to putting this knowledge into practice in the real world, even veteran traditional language students could have trouble.