There is a common belief, that it is better to start learning foreign languages as earlier as possible.
Some people consider that the best period of foreign language education is the primary school.
Others argue that there are crucial disadvantages of early learning.
Needless to say, that the best period of learning any languages is the age between 6 months and 1 year old.
The scientific researches have shown that children completely lose the ability to study languages after 8 years if they were not taught by parents or community.
It proves the theory of early education.
In childhood people are more perceptive to learning languages than in teen ages.
That is why children should be taught a foreign language in the meantime while they are learning their native language.
Hence, learning a foreign language at primary school would be more effective than at secondary school.
However, young children cannot study foreign language seriously, in order to succeed in lingual area all of new information should be given in playing form.
Additionally, intensive language learning can lead to mixing the grammar of foreign language and native one.
Furthermore, studying foreign language can cause pronunciation and semantic issues in mother tongue.
In conclusion, I believe that foreign languages should be taught as soon as possible.
From my private experience of teaching child Chinese, I tend to consider that it is more complicated to memorize new vocabulary and grammar after four years old than in early childhood.
The child who has already known some grammar rules and words order in his own language can hardly perceive naturally some new rules of foreign language.
Despite of some disadvantages of early lingual education, the opportunity to speak two or more foreign languages from childhood is priceless.