100+ Hard riddles to test your mental acuity

What can fill a room but takes up no space?

What is the only English word, with two synonyms that are antonyms of each other?

What kind of fish chases a mouse?

What word is pronounced the same if you take away four of its five letters?

What word in the English language uses all five vowels plus Y in alphabetical order, and uses each only once?

First, think of the color of the clouds. Next, think of the color of snow. Now, think of the color of a bright full moon. Now answer quickly what do cows drink?

Sara has four daughters, and each of her daughters has a brother. How many children does Sara have?

How much dirt is in a hole that's two feet by three feet?

What begins with an "e" and only contains one letter?

A girl has as many brothers and sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?

A plane crashed between the border of France and Belgium. Where were the survivors buried?

What five-letter word becomes shorter when you add two letters to it?

What runs, but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

If your uncle's sister is not your aunt, what relation is she to you?

I drive men mad for love of me, easily beaten, never free.