This Fluency Activity is a part of the Lesson 19, Unit 1, Grade 1. While using vocabulary words such as total and part is important for students' understanding of a concept, it is essential that students understand them. This is particularly important for English language learners. When using the words, point, gesture, or label these parts of the number sentence. Encourage students to use these words when talking about number sentences, too. Using them correctly demonstrates students' level of understanding.