I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

John went to a parrot shop in Mexico, and the parrot owner told him that his parrot is so unique that he repeats everything he hears. John got excited and immediately bought the parrot. John went home and spoke many words, but the parrot does not repeat anything.
He went again to the parrot shop and complaint to the shopkeeper, but the shopkeeper never lied. Explain?

With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?

I have branches, but no fruit, trunk or leaves. What am I?

What has no start, end, or centre?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

81 x 9 = 801. What must you do to make the this equation true?

What seven-letter word has hundreds of letters in it?

What do you call a fish without an eye?

When it's bad luck to meet a black cat?