Стр 73 упр 7 use the comparative degree of adjectives.

1.Microphones are put in different parts of the recording studio. The head of the microphone (1) is made of metal that forms an electromagnet. The sound (2) is recorded on tape as sound waves. Sound engineers make sure all the notes (3)are caught on tape. The tape (4) is divided into 16 tracks and each instrument (5) is recorded on a different track on the tape. Special effects (6) are added if necessary. The tape (7) is edited to make the final tape or 'master tape'. The master tape (8) is used to make a master disc and then copies (9)are made