You regulate the volume by adjusting the switch. Regulate = change something to and fro (in multiple directions) until it reaches a specific value Adjust = change something to something else (in one direction) Regulate = transitive verb; must have an object Adjust = transitive and intransitive.

adjust meaning (verb): change something slightly to make it more suitable for a new set of conditions or to make it work better 1- adjust something Watch out for sharp bends and adjust your speed accordingly. This button is for adjusting the volume. The brakes need to be adjusted. adjust something to something : Adjust your language to the age of your audience. 2 [intransitive, transitive] to get used to a new situation by changing the way you behave and/or think Synonymadapt They'll be fine—they just need time to adjust. adjust to something: After a while his eyes adjusted to the dark. adjust to doing something :It took her a while to adjust to living alone. It can be difficult to adjust to being a parent. adjust yourself to something: You'll quickly adjust yourself to student life. My eyes were still trying to adjust themselves to the strong sunlight. 3 [transitive] adjust something to move something slightly so that it looks neater or feels more comfortable He smoothed his hair and adjusted his tie. see also well adjusted regulate meaning as verb:{intransitive - transitive )regulate something to control something by means of rules The activities of credit companies are regulated by law. The government accepts whaling in principle as long as it is carefully regulated. It is up to the regulating authority to put the measures into effect. 2 [transitive] regulate something to control the speed, pressure, temperature, etc. in a machine or system This valve regulates the flow of water. dear if you want the answer in arabic just let me know......