Russian Clauses & Connectors
Что introduces information; чтобы points to a goal
Ask whether the second clause reports information or describes something someone wants to happen.
Я знаю, что он дома.
I know that he is home. The second clause tells us what I know; it has a finite verb.
Я учусь, чтобы лучше говорить.
I study so that I can speak better. When the subject is the same, чтобы can introduce an infinitive expressing purpose.
A requested action also uses чтобы: Она попросила, чтобы мы подождали. — She asked us to wait. With a different subject, the subordinate clause takes a finite past-form verb (подождали), not an infinitive. The form expresses the request, not past time.
Если is a condition; когда locates an event in time
Both can introduce a clause before the main statement, but they answer different questions.
Если будет дождь, мы останемся дома.
If it rains, we will stay home. Staying home depends on a condition.
Когда закончится урок, мы пойдём домой.
When the lesson ends, we will go home. The clause tells us when the next action takes place.
Compare a real possibility, Если будет время, я приду. (“If there is time, I’ll come”), with a hypothetical one, Если бы было время, я бы пришёл. (“If there were time, I would come”). Put a comma after the condition. The hypothetical uses бы with past-form verbs in both clauses; those forms do not necessarily refer to past time. For more on this pattern, see the conditional mood guide.
Context matters: когда can also mean “whenever” for repeated events. Don’t choose solely by translating the English word “when.”
Потому что gives a reason; поэтому gives a result
The same situation can be told in either direction. Notice where the explanation sits.
Мы остались дома, потому что шёл дождь.
We stayed home because it was raining. The subordinate clause explains why.
Шёл дождь, поэтому мы остались дома.
It was raining, so we stayed home. Поэтому introduces the result rather than a “because” clause.
Который adds information about a noun
The relative pronoun agrees in gender and number with the noun it refers to, while its case depends on its job inside the relative clause.
Я читаю книгу, которую ты мне дал.
I am reading the book that you gave me. Которую refers to feminine книгу and is accusative as the object of дал.
Это дом, в котором я живу.
This is the house in which I live. Котором refers to masculine дом; в takes the prepositional case for location.
Build it yourself
Я читаю статью + который / ты / написал → Я читаю статью, которую ты написал.
Статья is feminine singular; inside the second clause it is what you wrote, so который becomes accusative которую. Place the comma before the clause. The advanced drill asks you to assemble more complete sentences like this.
Read the pronouns guide for more forms. Russian commonly puts a comma before a subordinate clause, even where English does not.
Choose a practice level
Build foundations first, then use these connectors in full sentences with instant feedback.
Build questions and negative sentences before connecting clauses.
Practise beginnerChoose что, чтобы, если, and когда in complete sentences.
Practise intermediateWork with reasons, results, and relative clauses.
Practise advancedNeed to revisit sentence emphasis? Read the word order guide.