Verb conjugation of "pick" in English

Regarding the meeting in early May: I could not reschedule the appointment at my daughter's doctor and I will definitely know if I can come during the first 2 weeks. I guess we should talk next week.
I have three children, Michelle, Cathy and Joe. Unfortunately, my parents do not live in the area. I am glad that they visit every 2 weeks, although they are already over 70 years old.
Have you ever visited the U.S. before and if so, where have you been in the U.S.? I've been travelling in California, it was very amazing. We have traveled by car. Here are my corrections.