-ом / -ем
Singular Instrumental Forms
The instrumental singular answers Чиме? (With what?) or С ким? (With whom?). Class I nouns (masculine/neuter) end in -ом or -ем, while Class II nouns (ending in -а) always take -ом.
How It Works
The instrumental case in the singular (инструментал једнине) primarily denotes means/tools or social accompaniment.
1. Masculine and Neuter Consonant/-о/-е Stems (Class I):
• Hard stems: Take -ом:
град → градом, воз → возом, село → селом.
• Soft stems: Stems ending in palatals (ј, љ, њ, ћ, ђ, ч, џ, ш, ж) as well as the affricate ц systematically take -ем:
крај → крајем, муж → мужем, поље → пољем, лице → лицем, отац → оцем.
• Vowel Dissimilation (Masculine Nouns Only): When a masculine noun has a soft stem preceded immediately by the vowel е, the ending shifts from -ем back to -ом to prevent repetition of /e/. This is regular in monosyllabic roots:
Беч → Бечом, јеж → јежом.
In polysyllabic stems, both variants are frequently accepted in standard usage: месецом / месецем, падежом / падежем.
Important: Dissimilation does not apply to neuter nouns; neuter nouns in -е preceded by /e/ regularly retain -ем (e.g., предузеће → предузећем, решење → решењем).
• Exceptions to Dissimilation in Masculine Nouns: Masculine nouns ending in -тељ (e.g., пријатељ → пријатељем, учитељ → учитељем) and masculine nouns in -ац with a preceding /e/ after fleeting 'а' drops (e.g., Немац → Немцем, венац → венцем) regularly keep -ем.
2. Nouns ending in -а (Class II - feminine and masculine in -а):
• These nouns always take -ом, regardless of whether the stem consonant is hard or soft:
жена → женом, кућа → кућом, ружа → ружом, тата → татом.
3. Preposition vs. Bare Instrumental:
• Means / Tool: NEVER use с / са (e.g., пишем оловком, not *пишем са оловком).
• Accompaniment: ALWAYS require са / с (e.g., разговарам са сестром).
Examples (5)
- Путујемо возом за Нови Сад.
We are traveling by train to Novi Sad.
Word by Word: We-travel train-by to Novi Sad.
Masculine hard stem 'воз' takes bare '-ом' to express the means of transportation (no preposition).
- Марко шета парком са својом женом.
Marko is walking through the park with his wife.
Word by Word: Marko walks park-through with self's wife.
Accompaniment requires 'са', and feminine a-stem 'жена' takes '-ом'.
- Разговарао сам са својим најбољим пријатељем.
I spoke with my best friend.
Word by Word: Spoke am with self's best friend.
Nouns with '-тељ' take soft ending '-ем' without vowel dissimilation.
- Шетамо широким зеленим пољем.
We are walking through a wide green field.
Word by Word: We-walk wide green field-through.
Neuter noun 'поље' has a soft palatal stem in 'љ' and takes the ending '-ем'.
- Пишем овом обичном оловком сваки дан.
I write with this ordinary pencil every day.
Word by Word: I-write this ordinary pencil-with every day.
The tool/instrument 'оловка' takes bare '-ом' without any preposition.
Common Mistakes
Using the preposition 'са / с' when stating an instrument or vehicle
Пишем са оловком и путујем са аутом.Пишем оловком и путујем аутом.In Serbian, instruments and transport means take the bare instrumental without 'с/са'. The preposition 'с/са' denotes accompaniment or company.
Applying the soft ending '-ем' to feminine nouns ending in '-а'
Хвали се новом кућем.Хвали се новом кућом.Nouns ending in '-а' (Class II) always take '-ом' in the instrumental singular, even if the stem ends in a soft consonant (e.g., кућа → кућом, ружа → ружом, плажа → плажом).
Forgetting vowel dissimilation in masculine nouns when the stem already contains 'е'
Одушевљен сам Бечем.Одушевљен сам Бечом.When a soft-stem masculine noun has 'е' in its preceding syllable (like 'Беч', 'јеж', or 'месец'), the suffix dissimilates from '-ем' to '-ом' to avoid two consecutive 'е' syllables.
How It Connects
Learn This First
To correctly apply the instrumental singular endings (-ом, -ем, and -ом after feminine -а stems), learners need an understanding of grammatical gender and noun stem types, along with knowing the basic semantic functions of the instrumental case.
Related Patterns
- са / с + InstrumentalDoing Things with Someone
Explains when accompaniment requires 'с' versus 'са' with these singular forms.
Level 2 - Plural Instrumental
Shows how plural endings (-има / -ама) contrast with singular instrumental forms (-ом / -ем).
Level 2 - Masculine Nouns Ending in a Consonant
Details the base forms of masculine consonant nouns that take these instrumental endings.
Level 1
Learn Next
Patterns that build on this one.