[FFE 영어오답노트] AT THE FIRST / ON THE FIRST / IN THE FIRST

at the end = at the time when something ends

   at the end of the movie

   at the beginning of January

in the end = the final result of a situation = Finally

   At first everything is ok. but we had a lot of problems with our car , in the end we sold it.

   At first ~ in the end ~ 처음에는 ... 결국 나중엔...  

 

 

AT THE FIRST / ON THE FIRST / IN THE FIRST

at the first = as the first time

on the first = as the first event

in the first = as the first step/part of a series

 

 

For example, 

  at the first opportunity

  on the first fine day, on the first inspection,

  on the first day of Monday of each month.

  in the first four months of this year.