начальной

начальной

"Начальной" means "initial" or "primary."

Here, 'начальной' is used as an adjective describing 'школе' (school) and pertains to the initial stage of education, indicating an elementary school.

В начальной школе дети изучают основы математики.

In elementary school, children study the basics of mathematics.

In this context, 'начальной' is an adjective modifying 'частью' (part), signifying the initial phase of a project.

Начальной частью проекта была разработка дизайна.

The initial part of the project was the design development.

Here, 'начальной' operates as an adjective describing 'сложности' (difficulty), referring to the beginner or initial level of complexity.

Новые ученики были удивлены уровнем начальной сложности теста.

New students were surprised by the level of initial difficulty of the test.