Verb conjugation of "rinse" in English

On Thursday I have an appointment. If there is no other way, I'll move it. Can you meet on Tuesday, April 11, anyway? I suggest 10.30 in the morning, but I'm fairly flexible, so noon is good too.
The conjugations of verbs are the biggest problem for me. I have never studied Spanish in school, but visited evening classes instead. This year I want to take a full Spanish course.
I need to learn a lot of Spanish because I want to study at the university of Madrid. In Switzerland, I studied law, but after 2 years I have switched to medicine: to help people, rather than you know....