Maths
If you multiply this number by any other number, the answer will always be the same. What number is this?
Zero
What has a mouth but cannot chew?
River
I'm tall when I'm young and short when I'm old. What am I?
CANDLE
A word I know, Six letters it contains. Subtract just one, and twelve is what remains.
Dozens
https://www.riddles.fyi/hard-riddles/
When I take five and add six, I get eleven, but when I take six and add seven, I get one. What am I?
What is a CLOCK?
If you have me you want to share me, if you share me you won't have me. What am I?
What is A SECRET
what does the numbers 11, 69, 88, 96 all have in common?
they are all read the same upside down
What flies when it’s born, lies when it’s alive, and runs when it’s dead?
a snowflake
The more there is the less you see.
Darkness
What is a mathematician favorite dessert?
pi
I am an animal, named after the animal I eat. What am I?
Anteater
What kind of room has no windows or doors?
Mushroom
What starts with "t" ends with "t" and is filled with t
teapot
What can you catch but not throw?
COLD
I come from a mine and get surrounded by wood. Everyone uses me, what am I?
a pencil