Language acquisition, especially the second language acquisition, is never a pure cognitive process. So, the abilities of listening, speaking, reading, and writing are considered to have the same weight. I do not agree with this view.

The core function of language lies in communication, which inevitably leads to the procedures of processing and response to the input (listening and reading) and output (speaking and writing) of information respectively. Therefore, many language learners are convinced that people need to give the same level of attention to these four skills in order to achieveproficiency in the language they are learning. However, despite its rationality, this opinion cannot be discussed metaphysically.

Realistically, it is generally only language majors and those people working in the language industry that devote a significant amount of time to language learning. A much larger number of people may only study languages for specific working purposes. It would be an overkill to give the same weight to these four competencies. For example, in a foreign company whose main business is mechanical engineering, many professionals do not have to speak English fluently, as the public might think, but rather, being able to read designs and reply emails well is enough to get the job done. So, spending time to improve listening or speaking may just be the icing on the cake but not materially help to advance their work; instead, they need to put more efforts on reading and writing. By the same token, listening and speaking are more important to a qualified international tour guide than reading and writing, because these two language skills are relatively more interactive and better suited to the realities of the job.