Grammar in brief: With a friend, by bus

1At a glance

Ask: with whom? with what? by what? Then it’s -⁠la. “Where?” is -⁠da, though English says “on the bus” for both: otobüste is where you’re sitting, otobüsle is how you’re getting there.

With whom? Can’la

It answers: kiminle? — with whom?
In English: “with”: with Mum, with a friend
Example: Kızımla parka gidiyorum — I’m off to the park with my daughter
Its quirk: pronouns take it on “whose”: benimle, seninle, but onlarla

With what? By what? otobüsle

It answers: neyle? — with what? how?
In English: “with” or “by”: with a pen, by ferry
Example: Taksiyle geliyorum — I’m coming by taxi
Its quirk: and how you pay: kartla — by card

And Ayşe ile Can

It answers: no question: it stands between two words
In English: “and”
Example: Annem ile babam evde — Mum and Dad are at home
Its quirk: loves arasında: okul ile park arasında — between the school and the park

2The key points

İle comes after the word, not before it the way “with” does. Write it apart or grown on, it means the same: Can ile is Can’la.
Grown on, ile is -⁠la or -⁠le. Just two teams, like -⁠lar: vapurla, but trenle.
After a vowel a y steps in: arabayla, Ayşe’yle. The separate ile doesn’t need one: Ayşe ile.
The l never turns into a t, and nothing softens before it: uçakla, kitapla. Fıstıkçı Şahap has no say here.
With a name it goes after an apostrophe, like any ending: Can’la, Ayşe’yle, Efe’yle.

3How it works

-⁠la goes on last, after -⁠lar and “my”: arkadaşlarımla, “with my friends”.

After “his” it’s the y again, as after any vowel. Not the n the cases take in arabasında and arabasına: -⁠la isn’t a case.

Deniz bugün kardeşiyle geliyor.— Deniz is bringing his brother today.

On an abstract word, -⁠la answers “how?”, just like “with pleasure”:

Çay içelim mi? — Memnuniyetle!— Shall we have a tea? — With pleasure!

“And” or “with”? Try ve in its place. If it fits, it’s “and”, and both are coming. If it doesn’t, it’s “with”: the sentence is about one of them, and the other comes along. And ile never joins two sentences: that takes ve.

Ayşe ile Can geliyor.— Ayşe and Can are coming.

Ayşe bugün Can’la geliyor.— Ayşe’s coming with Can today.

4In real life

— Alo, kiminle konuşuyorum?— Hello, who am I speaking to?

— Nakit mi, kartla mı? — Kartla, lütfen.— Cash or card? — Card, please.

Hadi, Kadıköy’e vapurla gidelim!Come on, let’s take the ferry to Kadıköy!

Bu hap suyla, aç karnına.This pill’s with water, on an empty stomach.

— Kiminle yaşıyorsun? — Kedimle.— Who do you live with? — My cat.

Annemle babam bu akşam bizde.Mum and Dad are round at ours tonight.

Simit çayla çok güzel.A simit is lovely with tea.

Seninle her yere!With you, anywhere!

5Where it’s easy to slip

Not like this	Like this	Why
İle Ayşe geliyorum.	Ayşe’yle geliyorum.	İle comes after the word.
Otobüste geliyorum.	Otobüsle geliyorum.	“By what” is -⁠la; -⁠da is “where”.
vapurle	vapurla	The last vowel, u, is a back one.
arabala	arabayla	After a vowel, a y steps in.
uçağla	uçakla	Softening only happens before a vowel.
arabasınla	arabasıyla	After “his”, -⁠la takes y, not n.

6Check yourself

Four questions, each with two or three rules at once: which case it takes, which team, whether it needs a y. Every wrong answer slips on exactly one.

1“— Who are you coming with? — My sister.” Fill the gap.

— Kiminle geliyorsun? — Kız ? geliyorum.

2“Can’s coming in Ayşe’s car.” Which is right throughout?

3“— Are you taking the bus to Bodrum? — No, we’re flying.” Fill the gap.

— Bodrum’a otobüsle mi gidiyorsunuz? — Hayır, ?

4“Mum and Dad are coming over to ours on the ferry.” Which is right throughout?