Compare and contrast structure words are transition signals which show the similarities or differences. Below are some common examples.
When making comparisons or contrasts, it is important to be clear what criteria you are using. Study the following example, which contrasts two people. Here the criteria are unclear.
Although this sentence has a contrast transition, the criteria for contrasting are not the same. The criteria used for Aaron are height (tall) and strength (strong). We would expect similar criteria to be used for Bruce (maybe he is short and weak), but instead we have new criteria, namely appearance (handsome) and intelligence (intelligent). This is a common mistake for students when writing this type of paragraph or essay. Compare the following, which has much clearer criteria (contrast structure words shown in bold).
| Similarities | Example |
| is similar to | Spring weather in Vancouver is similar to spring weather in Halifax. |
| both | Both Vancouver and Halifax have rain in the spring. |
| also | Halifax also has a rainy spring season. |
| too | Halifax has a rainy spring season, too. |
| as well | As well, Halifax has rainy spring season. |
| Differences | Example |
| on the other hand | On the other hand, winter is much colder in Halifax. |
| however | However, winter is much colder in Halifax. |
| but | Vancouver has a mild winter, but Halifax has a cold one. |
| in contrast to | In contrast to Vancouver, Halifax has a cold winter. |
| differs from | Halifax differs from Vancouver by having a cold winter. |
| while | While Vancouver has a mild winter, Halifax has a cold winter. |
| unlike | Unlike Halifax, Vancouver doesn't get much snow |