значительная часть

см. тж. в течение значительной части года

The soil is dry during much of the year.

For much of that time the number of spots on the Sun has been increasing.

A major portion (or part) of the earlier work was concerned with ...

Compression is responsible for the inversion in the Los Angeles basin during a good fraction (or part) of the year.

In much of this region yields of rice have doubled.

Источник: Русско-английский научно-технический словарь на Gufo.me