Dear sister Lizzie,
I am ... (your name), how have you been recently? I am very much concerned about your health because we are safe here in Vietnam but the virus is spreading widely in other countries. Our family is all healthy and life is slowly coming back to normal. During quarantine we have online classes, do you? Stay safe at home in ... ( a country) Lizzie. We all love you! Bless you!
Sincerely yours
(your name)