No, it doesn't.
It would be "down to earth" because the other doesn't mean anything in English. "Down to earth" means someone who is sensible and logical instead of being a dreamer with his "head in the clouds."
It can mean many things. You can "get down to" something, which means you can settle in and get started. You can be "down to earth," which means you're sensible and practical. We really need to know the rest of the phrase in order to define it properly.
This phrase is not used in Romeo and Juliet.
to flip a turtle upside down
The phrase 'let down' can be defined in a number of ways. Let down means to disappoint or fail to fulfill the expectations but can also mean to to lower, deflate or untie.
the belief that only the Earth should be studied and explored
Talk down to someone, insult their intelligence.
Nine tenths of the earth would mean ninety percent of the earth. Used in a phrase one could say: Nine tenths of the earth has some form of life on it. [though I doubt that fact is true.]
Moe lepo is a figurative term for the dead. Moe is to sleep or lie down and lepo is dirt, earth, or dirty. Literally the term means to sleep in the earth or to be an "earth sleeper." It can also be a a phrase used to refer to a dirty, lazy person.
It's a phrase used to refer to the enemies, such a terrorist as in saying that they have been taken down.
The phrase "hold it down" is often used to mean maintaining order, control, or stability in a situation. It can also imply staying grounded, reliable, or supportive in challenging circumstances.
Utterance of the phrase "slow down" is used to tell someone to drive more slowly. This phrase could be used in the case of a driver approaching a red light too speedily.