Gravity is a natural phenomenon
or
Mirages are a common desert phenomenon
Each time a new social media app is revealed to the world it becomes a phenomenon for a while and then slowly fades into unimportance
"In" is a preposition.
·In their exploration
·in their sacrifice
"Of" is a preposition.
·of the world
"To" is a preposition.
·to feel as one
Tell me if you think I missed any.
In colloquial English 'them" would be acceptable
In formal English 'they' is used accompanied by the corresponding auxilliary verb
So, you could also say Is everyone who works in this store as helpful as they are ?
