This is the 8443rd most frequent Japanese word.
慣らさ
"慣らさ" is the stem form of "慣らす," meaning "to accustom" or "to habituate."
Here, '慣らしたいと思っています' refers to the process of habituating animals to human interaction for better coexistence.
動物園の職員は動物たちを人々の存在に慣らしたいと思っています。
The zoo staff wants to acclimate the animals to the presence of people.
In this context, '慣らしていきます' is progressing through continuous practice to familiarize students with competing.
毎日の練習で、生徒たちを競技に慣らしていきます。
Through daily practice, the students are acclimated to the competition.
Here, '慣らさなければなりません' means 'must acclimate,' focusing on adapting oneself to new conditions.