Relacionar Columnas Talking About FunctionsVersión en línea Matching por Logos Sprachinstitut 1 The shelf is bolted to the wall with screws. 2 The function of the switch is to turn the machine on and off. 3 The bridge is supported by steel pylons. 4 The purpose of the backup file is to keep our data safe. 5 The airflow is regulated by the valve. 6 The vehicle is powered by the engine. 7 The purpose of the wheel is to steer the truck. The wheel steers the truck. The valve regulates the airflow. Steel pylons support the bridge. The engine powers the vehicle. Screws bolt the shelf to the wall. The switch turns the machine on and off. The backup file keeps our data safe.