Cinnabar is a bright red mineral that is the main ore of mercury.

The trunk road is the main route for long-distance travel.

The narthex is the entrance hall of a church, leading to the main hall.

The pipe opener is an important practice before the main event.

The preamble of the document provides an introduction to its main content.

The printed circuit board is the main component of electronic devices.

The subheading of the article provided a concise summary of the main points.

The author wrote a preface to introduce the main themes of the book.

Let's not get off topic and focus on the main issue.

The leitmotif in the movie represents the main character's inner struggle.