"Tu es en train de regarder les chiens."
Translation:You are looking at the dogs.
The phrase "être en train de + infinitive" is the nearest substitute for the English continuous tenses, to express that an action is in progress at the time you speak.
You have learned that "you are watching" usually translates to "tu regardes", but if French speakers wish to be precise about what's happening right now, they will use this phrase.
"John is studying English at university" (not at this moment, but generally). "Sheila is spending some time in the United States next autumn" (not at this moment, but next year). These are typical uses of the present continuous in British English. Will french allow en train de with these sentences? If not, then the en train de construction is not quite the same as the present continuous.
"Être en train de faire quelque chose" means one thing: to be in the process of doing something. So it can be used to stress the current situation when English would used it with the same meaning:
- Tu es en train de regarder les chiens is exactly what you are doing at this very moment
Habits or routine are expressed with the present tense:
- John étudie l'anglais à l'université.
Future perspectives are expressed with the near future or the simple future tense:
- Sheila [[va passer/passera] quelque temps aux Etats-Unis l'automne prochain.