Verb conjugation of "recycle" in English

Please do the following: 1. Open the email 2. Press the 'Edit' menu button, then choose 'Select All'. The entire message is blue now. 3. In the menu, choose 'Edit', then 'Copy' and open a new word document.
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.
The course was a bit tough because the teacher always gave lots of homework. We were upset about his behaviour. He was very arrogant towards all the students. It was simply no fun to study there.