Mars
Mars
mars
Mars. It has features that look like dried-up river beds, etc.
Mars is believed to have had liquid water in the past based on evidence from river valleys, lake beds, and minerals that form in the presence of water. This suggests that ancient Mars was more hospitable to life than it is today.
Earth
MARS
Mars is the planet thought to have had liquid water in the past based on various geological features such as canyons, river valleys, and mineral signatures found on the surface. These suggest that Mars likely had a more hospitable environment billions of years ago where liquid water could have existed.
The past participle is thought.
"Thought" is the past tense form of the verb "to think."
infinitive: think past: thought past participle: thought
Thought is already the past participle of "think".
The past of "think" is "thought."