Verb conjugation of "precisare" in Italian

I like to watch TV at night before going to bed. Sometimes it is important to me to do something senseless. If I'd read a book I would need to concentrate and my brain would be focused on a specific topic. I sometimes do not want that.
You have to be careful when you go on summer vacation. There are many dangers but the most dangerous one is the sun itself, because if you're not careful it may harm you. People underestimate the rays.
Thanks again for your letter. For now, the weather here is like it is in your country, ice cold. I will write you a letter in Spanish and in English. So you can compare the sentences.