Question

Rewrite The children, small seeds, might at any instant be sown to all the Martian climes as a metaphor.

Answer 1

The following sentence as a metaphor could look like this:

They saw old cities, lying just like children's delicate bones, among the blowing lakes of grass.

The metaphor here is "Lying just like children's delicate bones" because it implies meaning of the part "They saw old cities".

What I did was add commas where needed, so that the middle part, the "Lying just like children's delicate bones", was secluded, and could be used as a metaphor in that sentence.

I hope this helps!

(I saw the comment, so I turned the Cities sentence into a metaphor.)

Answer 2

This is already a metaphor. A metaphor is a figure of speech that describes an object or action in a way that isn't literally true, but helps explain an idea or make a comparison.