chiefly

/ˈtʃiːfli/📚 11296 14 1托福
You use chiefly to indicate that a particular reason, emotion, method, or feature is the main or most important one. 首要地

adverb [方式副词]主要地;首先

He's travelled widely, chiefly in Africa and Asia. 他游历了许多地方,主要在非洲和亚洲。

chiefly 出现在下面的课文中
Lesson 45 Of men and galaxies