He is walking the line between honesty and deception.

She is falling in line to buy concert tickets.

He towed the line and followed all the rules.

He walks the line every day.

She fell in line at the grocery store.

He toed the line and followed the rules.

The Balmer line is a series of spectral lines in the visible region of the hydrogen spectrum.

The narrow, hedge-lined road led us to a picturesque village.

The grind line on this knife is very precise.

The equinoctial line marks the point where the celestial equator intersects the ecliptic.