What do those lights signify?

Clouds signify the veil of the Most High.

What you think doesn't signify at all.

Titles and honours signify nothing to me.

Life's but a walking shadow, a poor player that struts and frets his hour upon the stage, and then is heard no more. It is a tale told by an idiot, full of sound and fury, signifying nothing.

Furrowed eyebrows signify wh-questions in most sign languages.

This is because you approach everything as a total person, with no loose ends hanging out to signify divided intentions.

Life is a tale, told by an idiot, full of sound and fury, signifying nothing.

What does this sign signify?

It is tradition to fly the flag at half mast to signify mourning.