Câu hỏi:

Read the text carefully, then choose the most suitable answers.

Music influences people in different ways or the same person differently at different times. Music may seem to influence people differently. That is because people can react differently to the music. We are able to apply a choosing process to the music we hear. If someone hates jazz, then a jazz piece with a positive effect will probably not make him feel good. A happy song might appear to make an angry person angrier, yet it is not the music itself that is creating the anger; rather it is the positive effect of the music. The angry person does not want to accept the song's happy feeling: it points out his already existing anger, and makes that anger come to the surface. When a piece of music is played and we are listening to it, our body, mind, and feelings are being affected. The musicians of ancient cultures such as China, India, Turkey and Greece understood the effects of music. In fact, Pathagoras, in ancient Greece, introduced a whole science that concerned them. Because the musicians of these ancient cultures understood these effects, they created music that was positive, uplifting, and beneficial. Once the effects of music are better understood, the next step is to gain a better understanding of the music around us, and what effect it is actually having.

The word "Once" has a close meaning to_____.