Cách sử dụng
The expression "fasten on" means to concentrate on or focus intensely on something. You can use it when you are talking about someone who is very interested in a particular thing and is paying close attention to it. For example, you could say "She fastened on the details of the painting, examining every brushstroke closely," or "He fastened on the key points of the argument and made a strong case for his position." It is a way to describe someone who is giving their full attention to something and really trying to understand it.