Codeswitching
People who speak more than one language may often switch language in the middle of the conversation. This is often referred to as "Code-Switching". Speakers might have any one of several different reasons for switching languages: Sometimes a particular language might seem more appropriate for the particular topic of the conversation, or for the person addressed in the conversation. Some switches occur because the speaker might associate certain ideas, emotions, or a point of view with experiences made in a certain language. Sometimes, words might be missing in one language. Quite often, speakers who are fluent in two languages will code-switch for stylistic effects, for example to emphasise certain parts of the conversation. The switch can last for a few sentences, or even for just a single word.
View and listen to examples of code-switching: