Language is an intrinsic virtue of a society which goes hand-in-hand with its culture. In order to become fluent at a language one should study the cultures and lifestyles of inhabitants of that region. I firmly agree with this idea for the following reasons.
I do believe that language is a set of words which when used logically and sequentially helps one to interact and communicate with others. But is this the only value that language provides? The purpose of language is not limited to a statement of ordered words, it holds the ability to build rapport with people emotionally. In other words, language is a medium to connect with people. And to establish relation with an individual, it is required to have some knowledge of his tradition. For instance, when I went on a Goa trip, before the trip I explored a few things about the lifestyles of people over there along with the customs. And it amazed me that how much that was helpful along with Konkani, their local language, in making friends over there.
Moreover, we can learn about a language through many resources like classes, online videos and thesausrus. However, the words and phrases that we get ourselves exposed to are only formal, that is, we are learning only formal version of that language. To make sure that we acquire fluency at a language and get command over it like a native speaker, it is necessary to learn the dialects and idioms. Aforementioned things are deeply associated with the history and heritage of the region to which a language belongs. A novice might not understand a statement including an idiom that is referenced to the battle of Ramayana when Lord Rama got victory over evil deeds of Ravana.
Though some people argue that having only brief understanding and studying basics of a language might pave a way for communication for tourists, I would conclude that the consideration of becoming proficient at a language requires the knowledge about the lifestyles and tradtions of a nation.