1. Inside = “in”
2. Open Space = pointing 
3. Time = eliminate "in"
4. Location = eliminate "in"
5. Directional Verb = "enter" 

Inside = "in"
We now in car. 
(We are in the car.)

Find information in book.
(Find information in the book.)

Open Space = pointing
They swim pointing river.
(They swim in the river.)

Dogs finish play pointing park.
(The dogs played in the park.)
​

Time = eliminate "in"
I born 2000.
(I was born in 2000.)

They will see you one hour.
(They will see you in an hour.)

Location = eliminate "in"
I live city.
(I live in the city.)

They live apartment. 
(They live in the apartment.)

Directional Verb = "enter"
Pointing person broke enter my car.
(The person broke in my car.)

They enter house.
(They got in the house.)