In some of the words in this task (tugs, frogs, and flows), the final s makes the /z/ sound. When students read these words the slow way, they may pronounce the final s as either /sss/ or /zzz/; either way is acceptable. When they read these words the fast way, however, they should pronounce the final s only as /z/.
This task introduces students to “fill-in-the-blank” reading. That’s when an instructor pauses their fluent reading to allow the student to supply the next word or phrase.
In this case, you’ll read the passage as the student follows along with their finger. Pause after you read we on the final line, and allow the student to say the final word fast: leave.