1-C. Someone looking for a portable system can choose from hundreds of different earphones, headphones, and digital players that come in a range of colors, shapes, and sizes.Someone looking for a portable system can choose from hundreds of different earphones, headphones, and digital players that come in a range of colors, shapes, and sizes.
2-C. Interest in portable audio really started to take off in the 1980s with the development of personal music players that allowed listeners to enjoy music through headphones while walking outside.Interest in portable audio really started to take off in the 1980s with the development of personal music players that allowed listeners to enjoy music through headphones while walking outside.
3-C. M: Hey, Susan, how about those headphones?M: Hey, Susan, how about those headphones?
M:ねえ、スーザン、それらのヘッドフォンはどうでしょうか?
4. These headphones are for people who need headphones when performing aggressive dance.These headphones are for people who need headphones when performing aggressive dance.