The preschool that I am working at, there are a lot of foreign children, and their first language is not English. Communication for them is hard in the class. However, their language in play seems more advanced than it does in real life. They don't afraid to make mistakes, and they are much more confident to speak what they have learned or heard in the class. Sometimes, I have no idea what they are talking about, or what they want, but their friends who are English speakers can just easily help them translate to me by looking at their friends' facial expressions or gestures. For second language learners, the rich visual and contextual cues that are characteristic of play are helpful in expressing and understanding language meanings. Play provides a rich context for second language learners to make sense of and through language.

"Not surprisingly, many students who do not speak English fall behind in their studies early, because they are not taught content in their native language."(ASCD 1995,16)
As a teacher, if you don't speak your students' first language, you could recruit other children in you class, older children, family members, or volunteers to act as first language play partners.