they are right, Swift's clutch cannot be adjusted. It can only be slightly adjusted at the time of replacing the clutch plates.
Signs of a weak clutch are: the car shows higher RPM, but the speed is low. Engine makes more sound but car is not going that fast. and lastly to test clutch health, start the car, keep the brakes pressed and put the car in first or second gear and release the clutch.. if the car stalls immediately as your clutch is good, but if it takes time to shut off or does not shut off at all...clutch is bad