The proverb, "The cure for boredom is curiosity; there is no cure for curiosity." means that you will never be bored if you are curious because curiosity can never be taken away.
Sorry, it's only one sentence!! It's a start, though, and maybe it could help you to write the other 4 sentences.
A seven letter word containing thousands of letters - a mailbox.
The word mailbox has 7 letters, and it contains thousands of letters - just not the letters from the alphabet, but rather a form of a paper message.
Explanation:
HOPE THIS WILL HELP U
ND PLZ FOLLOW ME...........
B THE ANSWER IS BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
Cushion: Have you ever had a

job?
Chew: I can't

this.
Bushel: Their are dry measures of

.
Bamboo: I have seen a

forest.
Mildew: Are their any signs of

?
Soothe: I have

someone before.
Barefoot: I was running around outside

.
Renewal: Why is their a

in war?