The first job: not really related to my studies, stressed me at certain periods, good salary, but no guaranties of a longer contract. This is an assistant job

The second: in the field of my studies, teaching mainly, pays a little less, guaranteed: long contract

What do l choose??????????

l know that a little decision can affect my future.

l am an English graduate.

go with the job that you find more fulfilling.the one that you would love to do..go with the one that brings you the most happiness. when you love what you do, it is no longer a job.

The second choice

If l were in your situation l would take 2.
You seem more positive about this one. Remember money is not everything! You will have a easier life if your not stressed, it lies within your interests and there is a long contract.
Go for what feels right.

Take out the money from the equation.

What is your passion, what will make you feel complete and happy. That will be the job you want to take. l have seen many people in excellent paying jobs(myself included) and so extremely unhappy in the environment.

l am not going to completely decide for you because my mother took a job that was temp (b4 l was born!) and she met my dad, the love of her life..
life is unexpected
But based on your career, l would choose option number two because it has a brighter future and more chance to help you accelerate your career. You can never start at the top of the ladder, you have to work your way up..
good luck
♥

In the uncertain times we are in l would have to go with the ''long contract'' job because you almost guaranteed to have a job while the other job can be almost temporary,