Verb conjugation of "ralentir" in French

I want to improve my level of English. Have you ever been in the U.S. and in which states have you been? I've been in England, Scotland and Ireland, but unfortunately, I have never been to America.
The system will collect information about the learning behavior and guide the user through a tailor-made process that is best suited for him. This technique is not entirely new but we are redesigning the whole concept of it.
I was 10 days on vacation. We were in Portugal and Spain. It was very useful because I could improve my Portuguese, a little bit at least. Please send me pictures of your vacation too.