Verb conjugation of "retain" in English

The connecting flight to Phuket was fully booked, and the connection to Krabi had five empty seats. The problem was that the boarding began in ten minutes and I did not even have a ticket.
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.
I have learned German for one year and I would like to intensify my studies. Do not know how yet... It is very difficult at my age to start new projects in life. I am over 75, did I tell ya...