The Czech Instrumental: jedu tramvají, káva s mlékem
Prague runs on trams, and trams run on the instrumental. This case marks the tool, the vehicle and the companion — the by-and-with case.
How You Travel
Transport takes the bare instrumental — no preposition at all. The ending IS the "by":
Jedu autobusem. Jedu tramvají. Jedu metrem.
I'm going by bus. By tram. By metro.
Note: No little word needed — the ending does everything.
The Endings
The questions: kým? (with whom) čím? (by what).
With: s + Instrumental
s — with: s kamarádem (with a friend), s mlékem (with milk), se sestrou (s grows an e before another s-sound). Your coffee order graduates: káva s mlékem, čaj s cukrem.
Jdu do kina s kamarádem.
I'm going to the cinema with a friend.
Note: do kina (genitive) + s kamarádem (instrumental) — two cases, one evening.
Riding Like a Local
MHD — public transport. Buy a jízdenka (ticket) and validate it — označit si jízdenku — in the little yellow box, or carry Prague's pass, the lítačka. Plainclothes inspectors (revizoři) are a genuine ecosystem.
Common Mistakes
- na autobusem / v tramvají. No preposition for transport — jedu autobusem, plain and clean.
- s kávou for "coffee with milk". The milk is with the coffee: káva s mlékem — the s attaches to the addition.
- Forgetting -í for soft feminines. tramvaj → tramvají, ne tramvajem.
What You Can Do Now
You can name your ride without a preposition, bring a friend along with s + instrumental, order coffee properly dressed — and validate your jízdenka before the revizor asks.