Students can struggle to understand and use terms that describe probabilities. Such struggles lead to difficulties comprehending classroom conversations. In this article, we describe some specific misunderstandings a group of students (ages 11-12) held in regard to vocabulary such as "certain", "likely" and "unlikely". We discuss our efforts to help the students use such terms appropriately. In particular, we show how engaging students in a game requiring the use of the terms helped them begin to develop their vocabulary more fully. We also explain how a probability ladder visual organizer helped students begin to organize their thinking about the meanings of terms relative to one another.