How to use "expert" in a sentence

When the captain of the American ship the Abraham Lincoln decided to leave and look for the monster, he asked me to go with them as an expert.

Bill Jaborski had been a wilderness expert and a scoutmaster

However, I had become expert at overcoming this fear and had trained myself to speak calmly, no matter what said to me

'Of course, when the expert saw the silver, he would know it wasn't the real thing, and then Colonel Protheroe would remember that he had shown the things to Dr Stone...'

'We got an expert to look at it - to say whether the 6.20 was written by someone else