Culture impacts language at a number of levels. First, culture will affect an individual's nonverbal behavior. In the U.S. culture, one example of kinesics (gestures) is giving someone a thumb's up. This individual is sending a message that is positive. It could mean "good job" or "I like what you are doing." However, in Iran or Iraq, giving someone the thumbs up is very negative. http://www.articlesbase.com/travel-tips-articles/the-meaning-of-the-thumbsup-hand-gesture-around-the-world-624721.html
Additionally, culture can affect the other type of nonverbal communication: paralanguage. Paralanguage are the vocalizations that accompany speech in both formal and informal situations. This includes nonmeaningful sounds like "um" and "uh". It can also include tone and pitch of your voice as you speak. For example, in the U.S. we tend to laugh or giggle when things are funny or when we are nervous. In Japan, a giggle means you are embarrassed. Also, facial expressions convey nonverbal meaning. Smiling is commonplace in the U.S., but in many Asian cultures smiling is a suppressed facial expression. http://www.andrews.edu/~tidwell/bsad560/NonVerbal.html
Culture also impacts language development in the verbal area as well. The Sapir-Whorf hypothesis claims that thoughts and behavior are impacted by language. ...
Culture impacts learning on every level. It especially impacts a child's ability to acquire language.