In Esperanto, as in English, adjectives and adverbs can be used for comparing one item with others. Here are some examples in English:
The comparative in English is formed with either the suffix “-er” or the separate word “more”. The superlative is formed with either the suffix “-est” or the separate word “most”. Esperanto has only one way of forming these: the separate words pli for the compative, and plej for the superlative. As you can see, adverbs compare in the same way as adjectives.
Where English uses the word “than” in comparisons, Esperanto uses the word ol.
| 1a | Petro | estas | pli forta | ol | Marko. |
| Peter | is | stronger | than | Mark. |
| 1b | Roberto | estas | la plej altkreska | knabo | en | la lernejo. |
| Robert | is | the tallest | boy | in | the school. |
| 1c | Elizanjo | kantas | pli bele | ol | Rivka. |
| Lizzie | sings | more beautifully | than | Becky. |
| 1d | Sara | pentras | la plej belajn | pentraĵojn. |
| Sarah | paints | the most beautiful | paintings. |
Negative comparisons in English are made with the words “less” and “least”; Esperanto uses the words malpli and malplej.
| 2a | Haroldo | estas | malpli amika | ol | Timoteo. |
| Harold | is | less friendly | than | Timothy. |
| 2b | Ĥana | faras | la malplej ĉarmajn | skulptaĵojn. |
| Hannah | makes | the least attractive | sculptures. |
You probably noticed that the Esperanto words for “less” and “least” appear to be simply the words for “more” and “most” with the prefix mal- attached. That is precisely the case. In fact, this prefix can be used to form the opposite of nearly any word, and this is another factor that reduces the size of Esperanto’s root vocabulary.
| Basic word | Opposite |
|---|---|
| fort/a = strong |
mal/fort/a = weak |
| jun/a = young |
mal/jun/a = old |
| amik/o = a friend |
mal/amik/o = an enemy |
| amik/a = friendly |
mal/amik/a = unfriendly |
| ferm/i = to close |
mal/ferm/i = to open |