Compare each pair of words and complete the following sentences with the right one. Change the form if necessary.
1) own, owner
His father ___________ a big factory.
I am the ___________ of these three cars.
2) compete, competition
There was a lot of ___________ between my brother and me when we were kids.
We are too small to ___________ with a company like that.
3) existence, exist
Jones led a lonely ___________ in a village for several years.
People can't ______ for long without water.
4) apologize, apology
I ___________ for taking so long to reply.
We would have been happy with an _______.
5) threat, threatening
Pollution has become a great _______ to our daily life.
She's been receiving _________ phone calls lately.