Instrumental Case (Instrumentál)

Question: S kým? S čím? (With whom? With what?)

The Instrumental expresses the means by which something is done, or accompaniment (with).

Core Concept: The Instrumental = MEANS / ACCOMPANIMENT

The instrumental has two fundamental meanings:

1. Means/Instrument: HOW something is done: Píšu perem (I write with a pen)
2. Accompaniment: WITH whom: Jdu s Petrem (I go with Peter)

Extended meanings flow from these:

• Location: where something passes: Jdu lesem (I go through the forest)
• Identity/Role: who someone is: Jsem učitelem (I am a teacher)
• Time: during when: Ráno vstávám (I get up in the morning — ráno is instr.)

The key insight: Instrumental answers "with what/whom?" or "by what means?"

At a Glance (Singular)

Which Ending? Follow the Flowchart

The instrumental is one of the easiest cases — most nouns just take -em:

---

Memory Aids (Mnemonics)

Use these tricks to remember the patterns you just saw in the cheatsheets above.

The "-em" Dominance

For masculine and neuter nouns, the ending is almost always -em:

• pánem, mužem, hradem, strojem
• městem, mořem

Memory: "Masculine and Neuter are EM-bros"

Feminine Splits: -ou vs -í

Feminine Type	Ending	Examples
Hard stem (-a)	-ou	ženou, knihou, vodou
Soft stem (-e, consonant)	-í	růží, písní, kostí

Memory: "Hard A becomes OU, Soft gets Í"

Plural Patterns

Gender	Ending	Examples
Masc/Neut hard	-y	pány, hrady, městy
Masc/Neut soft	-i	muži, stroji, moři
Feminine	-ami/-emi/-mi	ženami, růžemi, kostmi

Memory: "Feminine plural adds -MI to the party"

---

S vs No Preposition — When to Use "With"

One of the trickiest aspects of the instrumental is knowing when to use s/se and when to go without it.

When to Use S/SE (Accompaniment)

Use s/se when expressing accompaniment or together with:

Context	Example	Meaning
People	Jdu s Petrem.	I'm going with Peter.
Items brought	Káva s mlékem.	Coffee with milk.
Togetherness	Bavím se s přáteli.	I'm chatting with friends.
Mutual action	Mluví se mnou.	He's talking with me.

When NOT to Use S (Means/Instrument)

When expressing means, instrument, or manner, use bare instrumental:

Context	Example	Meaning
Writing tool	Píšu perem.	I write with a pen.
Transport	Jedu autem.	I go by car.
Body part	Mává rukou.	She waves with her hand.
Language	Mluví česky. (adverb)	But: Mluví češtinou.
Method	Pracuje rukama.	He works with his hands.

Common Mistake

❌ Jedu s autem. (going with a car — implies the car is a companion!) ✅ Jedu autem. (going by car — car is the means)

The difference:

• s = accompaniment (someone/something comes along)
• no preposition = instrument/means (how you do it)

S vs SE — When to Add E

Form	When to Use	Examples
s	Before most consonants	s Petrem, s knihou, s maminkou
se	Before s, z, š, ž, and clusters	se sestrou, se Zuzanou, se mnou

Rule: If "s + word" would be hard to pronounce, use "se".

---

Special Uses of the Instrumental

1. Predicate Instrumental (Identity/Profession)

Used with být to express profession, role, or identity:

Czech	Literal	Natural English
Jsem učitelem.	I am a teacher.	I am a teacher.
Stal se lékařem.	He became a doctor.	He became a doctor.
Zůstal přítelem.	He remained a friend.	He remained a friend.

Nominative vs Instrumental with Být

• Nominative (more casual/temporary): Jsem učitel.
• Instrumental (more formal/permanent): Jsem učitelem.

Both are correct, but instrumental sounds more formal and emphasizes the role.

2. Movement Through/Along

Bare instrumental can express movement through or along:

Czech	English
Jdu lesem.	I walk through the forest.
Běží ulicí.	He runs along/through the street.
Pluje řekou.	He sails along the river.
Letí oblohou.	It flies across the sky.

3. Time Expressions

Some time words are in the instrumental:

Czech	English
ráno → ránem	in the morning (archaic, poetic)
večer → večerem	in the evening
nocí	at night
létem	in summer
zimou	in winter

More commonly: ráno, večer, v noci, v létě, v zimě (nominative/locative)

---

Prepositions That Require Instrumental

Location Prepositions (Static Position)

These take instrumental for static location:

Preposition	Meaning	Example
za	behind	Za domem. (Behind the house.)
před	in front of	Před domem. (In front of the house.)
pod	under	Pod stolem. (Under the table.)
nad	above	Nad stolem. (Above the table.)
mezi	between	Mezi oknem a dveřmi. (Between the window and the door.)

Motion vs Static

Remember: these same prepositions take accusative for motion:

• Jdu za dům. (I'm going behind the house.) — motion = accusative
• Jsem za domem. (I'm behind the house.) — static = instrumental

Other Prepositions

Preposition	Meaning	Example
s/se	with	S přáteli. (With friends.)
před	before (time)	Před hodinou. (An hour ago.)
za	in (time - past conditions)	Za deště. (In the rain.)

---

Usage

1. Means / Instrument (How?)

No preposition!

• Píšu perem. (I write with a pen.)
• Jedu autem. (I go by car.)
• Platím kartou. (I pay by card.)
• Krájím nožem. (I cut with a knife.)

2. Accompaniment (With whom?)

Use preposition s/se.

• Jdu s Petrem. (I am going with Peter.)
• Káva s mlékem. (Coffee with milk.)
• Bydlím s rodiči. (I live with my parents.)

3. Predicate Instrumental

Used with the verb být to express a profession, role, or temporary state.

• Jsem učitelem. (I am a teacher.)
• Otec je lékařem. (Father is a doctor.)
• Stala se vědkyní. (She became a scientist.)

4. Location Prepositions (Static)

• Za (behind): Za domem. (Behind the house.)
• Před (in front of): Před domem. (In front of the house.)
• Pod (under): Pod stolem. (Under the table.)
• Nad (above): Nad stolem. (Above the table.)
• Mezi (between): Mezi oknem a dveřmi. (Between the window and the door.)

---

Detailed Reference Tables

Singular Endings

Gender	Model	Ending	Example (Nom → Instr)
Masc Animate	pán	-em	pán → pánem
	muž	-em	muž → mužem
Masc Inanimate	hrad	-em	hrad → hradem
	stroj	-em	stroj → strojem
Feminine	žena	-ou	žena → ženou
	růže	-í	růže → růží
	píseň	-í	píseň → písní
	kost	-í	kost → kostí
Neuter	město	-em	město → městem
	moře	-em	moře → mořem
	kuře	-etem	kuře → kuřetem
	stavení	-ím	stavení → stavením

Rule of Thumb

• Masculine and Neuter: -em (easy!)
• Feminine hard (-a): -ou
• Feminine soft: -í

---

Plural Endings

The Instrumental Plural follows a simple pattern based on hard/soft stems.

At a Glance (Plural)

Endings by Gender

Gender	Hard Stem	Soft Stem	Examples
Masculine	-y	-i	pány, hrady, muži, stroji
Feminine	-ami	-emi/-mi	ženami, růžemi, kostmi
Neuter	-y	-i	městy, auty, moři

Simple Pattern

• Masculine & Neuter: hard -y, soft -i (like nominative plural!)
• Feminine: always ends in -mi (ženami, růžemi, kostmi, písněmi)

The feminine ending is longer and distinctive!

Examples

Masculine:

• Jdu s přáteli. (I'm going with friends.)
• Pracuji s nástroji. (I work with tools.)

Feminine:

• Mluvím s ženami. (I'm talking with women.)
• Ozdobeno růžemi. (Decorated with roses.)

Neuter:

• Mezi městy. (Between cities.)
• S kuřaty. (With chicks.)

---

Verbs That Require Instrumental

Several verbs inherently require the instrumental case for their object or complement.

Verbs of Becoming/Being

Verb	Meaning	Example
být	to be (formal)	Je lékařem. (He is a doctor.)
stát se	to become	Stal se prezidentem. (He became president.)
zůstat	to remain	Zůstal přítelem. (He remained a friend.)

Verbs of Movement

Verb	Meaning	Example
hýbat/pohnout	to move	Hýbe rukou. (He moves his hand.)
otáčet	to turn	Otáčí hlavou. (He turns his head.)
mávat	to wave	Mává rukou. (She waves her hand.)
kývat	to nod	Kývá hlavou. (He nods his head.)

Verbs of Control/Ruling

Verb	Meaning	Example
řídit	to control/drive	Řídí firmou. (He runs the company.)
vládnout	to rule	Vládne zemí. (He rules the country.)
disponovat	to have at disposal	Disponuje penězi. (He has money at his disposal.)

Verbs with S + Instrumental

Verb	Meaning	Example
souhlasit s	to agree with	Souhlasím s tím. (I agree with that.)
počítat s	to count on	Počítám s tebou. (I count on you.)
zacházet s	to treat/handle	Zachází s ním špatně. (He treats him badly.)
bavit se s	to chat with	Bavím se s přáteli. (I chat with friends.)
seznámit se s	to meet	Seznámil se s ní. (He met her.)

---

Common Errors and How to Avoid Them

1. Using S When Not Needed

❌ Píšu s perem. → ✅ Píšu perem. (instrument = no S) ❌ Jedu s autem. → ✅ Jedu autem. (means of transport = no S)

Rule: S = accompaniment (coming with); no S = instrument/means

2. Wrong Ending for Feminine

❌ s žení → ✅ s ženou (hard stem = -ou) ❌ s růžou → ✅ s růží (soft stem = -í)

3. Using Accusative for Static Location

❌ Jsem pod stůl. → ✅ Jsem pod stolem. (static = instrumental) ❌ Je to za dům. → ✅ Je to za domem. (static = instrumental)

Rule: Kde? (where?) = instrumental; Kam? (where to?) = accusative

4. Forgetting S → SE Before Certain Consonants

❌ s sestrou → ✅ se sestrou (before s-) ❌ s Zuzanou → ✅ se Zuzanou (before z-) ❌ s mnou → ✅ se mnou (always se mnou!)

5. Wrong Plural Feminine Ending

❌ s ženy → ✅ s ženami (feminine plural = -ami/-emi/-mi) ❌ s kosti → ✅ s kostmi (short form for kost type)