The following tables are meant to give some idea of the number and variety of different ideas that can be expressed by a single Esperanto root, with the addition of affixes (prefixes and suffixes). By reading the English, French, and German columns downwards, the reader will see how many different roots and periphrases these languages employ in order to express the same ideas.
As the affixes have fixed meanings, they only have to be learnt once for all, and many of them (e.g. -ist, -in, re-) are already familiar. When once acquired, they can be used in unending permutation and combination with different roots and each other. The tables below are by no means exhaustive of what can be done with the roots san- and lern-. They are merely illustrative. By referring to the full [table of affixes] the reader can go on forming new compounds ad libitum: e.g. san‑o, san‑a, san‑e, san‑i, saneco, sanilo, sanulo, malsane, malsani, saneti, malsaneti, sanadi, eksani, eksaniĝi, saninda, sanindi, sanindulo, sanaĵo, sanaĵero, sanilo, sanigilo, sanigilejo, sanigilujo, sanigilisto, malsanemeco, remalsano, remalsanigo, sanila, malsanulino, sanistinedzo, sanilingo, sanigestro, sanigestrino, sanigema, sanega, sanigega, gesanantoj, saniĝontoj, sanigistido, sanigejano... and so on (kaj tiel plu).
| Affix | Esperanto | English | French | German |
| san‑a | healthy | bien portant | gesund | |
| mal- (opposite) | mal‑san‑a | ill | malade | krank |
| ne (not) | ne‑san‑a | unwell | (un peu) souffrant | unwohl |
| -ig (causative) | san‑ig‑i | to heal | guérir | heilen |
| san‑ig‑a | salutary | salutaire | heilsam | |
| re- (again) | re‑san‑ig‑a | restorative | restaurant | wiederherstellend |
| -iĝ (becoming) | san‑iĝ-i | to be convalescent | être convalescent | sich erholen |
| re‑san‑iĝ-a | getting well again | en train de se rétablir | genesend | |
| -ig | mal‑san‑ig‑a | sickening (transitive) | écoeurant (qui rend malade) | ekelhaft (krank machend) |
| -iĝ | mal‑san‑iĝ-a | sickening (intransitive) | languissant | siechend |
| -ist (agent) | san‑ig‑ist‑o | doctor | médecin | Arzt |
| -ej (place) | san‑ig‑ej‑o | hospital | hôpital | Krankenhaus |
| -ul (characteristic) | mal‑san‑ul‑o | invalid | un malade | ein Kranker |
| -ebl (possibility) | (mal)-san‑ig‑ebl‑a | (in)curable | (in)curable | (un)heilbar |
| -ar (collective) | mal‑san‑ul‑ar‑o | hospital inmates | ensemble des malades | Gesamtheit der Kranken |
| ge- (both sexes) | ge‑mal‑san‑ul‑ar‑o | all the men and women patients | les malades hommes et femmes | die Kranken beider Geschlechter |
| -in (feminine) | san‑ig‑ist‑in‑o | a lady doctor | un médecin femme | Arztin |
| -edz (married) | san‑ig‑ist‑edz‑in‑o | a doctor's wife | une femme de médecin | Frau des Arztes |
| Affix | Esperanto | English | French | German |
| lern‑i | to learn | apprendre | lernen | |
| -ig (causative) | lern‑ig‑i | to teach | enseigner | lehren |
| lern‑ig‑a | educative | éducateur | erzieherisch | |
| -ej (place) | lernej‑o | school | école | Schule |
| -ant (pres. part.) | lern‑ant‑o | pupil | élève | Schüler |
| ge- (of both sexes) | ge‑lern‑ant‑oj | pupils of both sexes | élèves des deux sexes | Schüler and Schülerinnen |
| -ar (collective) | lern‑ant‑ar‑o | class | classe | Klasse |
| -an (appertaining) | lern‑ej‑an‑o | schoolboy | écolier | Schulknabe |
| -in (feminine) | lern‑ej‑an‑in‑o | schoolgirl | ecolière | Schulmädchen |
| -estr (chief) | lern‑ej‑estr‑o | headmaster | proviseur | Direktor |
| -ist (agent) | lern‑ej‑ist‑o | schoolmaster | instituteur (professeur) | Lehrer |
| lern‑ej‑ist‑in‑o | schoolmistress | institutrice | Lehrerin | |
| -aĵo (concrete) | lern‑aĵ-o (learnt‑stuff) | subject | matière d'enseignement | Lehrstoff |
| lern‑aĵ-ar‑o | curriculum | ensemble des matières d'enseignement | (Studien)- Laufbahn Schulprogramm | |
| -em (inclination) | lern‑em‑a | studious | appliqué | fleissig |
| mal- (opposite) | mal‑lern‑em‑a | idle | paresseux | faul |
| -ig (causative) | lern‑em‑ig‑i | to stimulate | mettre en train | anregen |
| lern‑ig‑o | instruction (act) | instruction | das Unterrichten | |
| lern‑ig‑aĵ-o | instruction (teaching given) | enseignement | Unterricht |