immediately
If something happens immediately, it happens without delay.
We have to leave immediately. It's very urgent.
Rishi read the letter, and immediately started to cry.
If something happens immediately after something else, it happens as soon as the other thing is finished.
He had to go out immediately after lunch.
She left for the airport immediately after I spoke to her.
If something is immediately above something else, it is above it and very close to it. You can use immediately in a similar way with other prepositions such as under, opposite, and behind.
There is a window immediately above the door.
The man immediately behind me in the photograph is my father.