There are several common expressions for making contrasts in English. They include on the one hand … on the other hand, on the contrary, in comparison, by comparison, in contrast, by contrast.
On the one hand … on the other hand
We can use on the one hand and on the other hand when we contrast two different things or two different ways of thinking about something. We often use them to present a balanced argument in which both sides must be considered:
On the one hand, mobile phones are very useful and can save lives. On the other hand, people seem to use them for the most pointless and unnecessary calls.
We often use on the other hand on its own in the second part of a contrast, without on the one hand:
It’s a chaotic and disorganised country, but on the other hand it’s a very friendly and beautiful place. (Both things are true about the country.)
Not: … but on the contrary …
On the contrary
We can use on the contrary to emphasise that something is the opposite of something which has been mentioned. We often use it to state that an original statement was not true, and we often use it after a negative statement. On the contrary is much more common in writing than in informal speaking:
He didn’t seem offended by her criticisms; on the contrary, he seemed to enjoy them. (It was not true that he was offended by the remarks – he enjoyed them.)
In comparison and by comparison
We can use in comparison and, less commonly, by comparison to contrast two clauses or sentences. They indicate how people and things are different when we compare them side by side:
London is England’s biggest city. Its second city, Birmingham, in comparison, is quite small by global standards.
Driving the old model of this van was hard work. Driving the new model is easy in comparison.
Cynthia was very nervous. Martha was quite calm by comparison.
We can use in comparison with X, Y is … to make a contrast:
In comparison with his older brother, who never stops talking, he’s quite shy.
In contrast and by contrast
We use in contrast and, less commonly, by contrast to link two clauses. In contrast and by contrast stress the difference between two people or things more strongly than in comparison and by comparison:
Holistic medicine treats the whole person. Conventional medicine, in contrast, treats specific symptoms and parts of the body.
We can use in contrast to or, less commonly, in contrast with to contrast two noun phrases:
In contrast to most of the city’s museums, the art museum is modern, bright and has a friendly atmosphere.
The white roses looked lovely in contrast with the red ones.
By contrast is less common than in contrast. We can use it alone or followed by with, but not by to:
In the south much of the land is flat. By contrast, in the north there are hills and mountains everywhere.
By contrast with the external appearance of the place, the room into which the front door opened was, if not particularly attractive, clean and well ordered.