Cách sử dụng
The word 'ascertain' means to find out something or to discover the truth about something. You can use it when you want to make sure of something or to confirm something. For example, you can say "I need to ascertain if the information is correct before I make any decisions" or "I asked the doctor to ascertain the cause of my sickness." It is a formal word and is mostly used in professional or serious situations.