Timmy has a few "friends".
The first friend is a large body of water, but can be fit into two envelopes with one envelope left over. You can argue it's a verb, but it doesn't actually matter.
The second is an animal. It can be represented in the shortest way possible. Its name is pronounced without any accented e sound.
The third is in the stuff humans need. It's also in the lanterns of the world's sky. But here, on this planet, it's rarely alone.
The fourth, if you say its short name, sounds like something you often see. But Timmy lives in the 17th, so he never saw one. You can also say it's the stuff which protects (some parts of) some animals.
Process them through some kind of table (figure out yourself whether it's a time table, a dining table, or something else) and put them together, what do you get? The answer is a single word.
The 4th's full name contains more than 4 but does sound like something you often see if you say the name which contains less than 4.
More precisely, between 1 and 4 exclusive.
The final answer is a word consisting of $n$ letters where $n$ is a composite number less than 7.
The containses in the first beep refer to letters.
A specific trainer says the final answer.