1. The box like figure in the given image is the [BATTERY SOURCE] from where the current drawn into the circuit.
2. A string connecting positive terminal of battery to the bulb is an [ELECTRIC WIRE] through which current flows in the circuit.
3. A bubble like object in the circuit is a [BULB] which lights up when current moves through the circuit.
4. A component connected to the negative terminal of batter source is a [SWITCH].
The answer are uppercase.
I hope this helps c:
