1. Frequencies ranging from 300 to 3000 kilohertz are referred to as medium radio frequencies.
а) Participle I в функции определения
2. The alternating (а) Participle I в функции определения )current passes through a winding on a permanent magnet, causing (б) Participle I в функции обстоятельства) the magnetic field.
3. The seven digits are transmitted to the exchange by appropriate dialing.
г) герундий
4. At the moment we are using a modem linked up direct to our computer and the telephone line.
в) Participle I в составе временной группы Continuous
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