The verb spot means to see, to see, and especially to suddenly discover or notice
1. spot+ object
Can you spot the weakness in her argument?
Can you point out the deficiencies in her arguments?
Can you spot the difference between these two pictures?
Can you see how these two paintings differ?
It took a practised eye to spot the difference.
Only an expert can see the difference.
An expert with a trained eye will spot the difference immediately.
A well-trained and discerning expert will immediately see the difference.
They spotted a niche in the market, with no serious competition.
They see a less competitive opportunity in the market.
2.spot sb doing sth
He spotted her steaming down the corridor towards him.
He saw her scurrying down the hallway towards him.
Neighbours spotted smoke coming out of the house.
Neighbors noticed smoke coming out of the house.
Meg spotted someone coming out of the building.
Meg saw a man coming out of the building.
3.spot that从句
One of the station staff spotted that I was in difficulty, and came to help.
A station worker saw that I was in trouble and came to help.
I spotted a shooting star which, to my astonishment, was bright green in colour
I saw a shooting star, and to my great surprise, it was a bright green.
No one spotted that the gun was a fake.
No one noticed that it was a fake gun.