It involves transforming vocabulary into words or phrases which have the same or similar meaning as the original.
This can be done in two ways:
By different word families:
Our cities are becoming increasingly polluted.
can change to
Pollution is increasing in our cities.
Or with different vocabulary:
Yet the reality is nowhere near as appealing.
can change to
The truth, however, is far less attractive.
Here are some more examples of how sentences can be presented differently using parallel expressions:
The environmental impact of the increasing number of cars on the road is devastating.
Could be rewritten as:
The rise in the volume of cars being used is highly destructive to the environment.
Without a convenient and economical public transport system, most people will continue to use their cars to get to work.
Could be rewritten as:
The majority of commuters will not abandon their own private vehicle until mass transit options become more flexible and better priced.
The situation is intensified by the rising number of two-car families.
Could be rewritten as:
The problem has been heightened by the increasing number of households that own two vehicles.
Car-sharing schemes, where people travel together in one vehicle, have not been particularly successful.
Could be rewritten as:
Reducing the number of single occupant cars have not been a great success.
Although contaminants in petrol have been reduced, they still pose a significant threat.
Could be rewritten as:
Despite now having lower levels of contamination, petrol is still a notable concern.
The lack of government legislation to control exhaust fumes, especially from older cars, has exacerbated the problem.
Could be rewritten as:
The problem has been heightened, to a large extent from older vehicles, because there are insufficient laws to govern this.
In addition to environmental damage, increased air pollution has direct health consequences.
Could be rewritten as:
Airborne pollutants can have a clear impact on health as well as the effect on the environment as a whole.
Respiratory diseases have increased, especially within inner-city areas.
Could be rewritten as:
Those residing in urban areas are increasingly likely to suffer with breathing related conditions.
Benzene, a by-product of the combustion of petrol, has been linked to birth defects.
Could be rewritten as:
Complications arising from birth have been connected to benzene, a specific secondary result of burning gas.
Yet while the car retains its image of freedom and individuality, it is unlikely that people will opt to take the bus.
Could be rewritten as:
Public transport will probably not be used commonly until the use of private vehicles is no longer considered to represent a feeling of being unique and allowing people to travel freely.