Почему ты опаздываешь?

Why are you late?

Breakdown of Почему ты опаздываешь?

• ты: you
• опаздывать: to be late
• почему: why

Questions & Answers about Почему ты опаздываешь?

What does Почему mean?

Почему is the Russian word for “why,” used to ask for a reason or cause.

What is опаздываешь?

Опаздываешь is the second-person singular, present-tense, imperfective form of опаздывать, which means “to be late.” Together it means “you are being late” or simply “you’re late.”

Why is the verb in the present tense here?

Because the speaker is asking about something happening right now or habitually. If you wanted to ask “Why were you late?” you’d use the past­-tense perfective почему ты опоздал?

What’s the difference between опаздывать (imperfective) and опоздать (perfective)?

• Опаздывать (imperfective) describes an ongoing or habitual action: “to be late” (I keep being late, I’m late right now).
• Опоздать (perfective) describes a single completed event: “to have been late” or “to end up late.”

Why is ты included here? Isn’t the ending ­–ешь enough to tell who is late?

Russian verb endings do show the subject. Ты is optional and adds emphasis or clarity, especially in questions or when contrasting people. Without ты the sentence Почему опаздываешь? is grammatically fine but sounds more abrupt or poetic.

Could I change the word order, like Ты почему опаздываешь?

Yes, Russian word order is flexible.
• Почему ты опаздываешь? is neutral.
• Ты почему опаздываешь? emphasizes ты (“Why are YOU late?”).
• Почему опаздываешь ты? sounds poetic or confrontational.

How do I pronounce опаздываешь and where is the stress?

It’s pronounced [a-paz-DY­-vay­-esh] with the stress on the third syllable: опаздЫваешь.

How would I ask the same question politely or formally?

Replace ты with вы and adjust the ending:
Почему вы опаздываете?
This uses the second-person plural/formal conjugation of опаздывать.

How do I specify what someone is late for, e.g. “Why are you late for the meeting?”

Use на + accusative for events or appointments. For example:
Почему ты опаздываешь на встречу? (Why are you late for the meeting?)
Or with к + dative for people or places:
Почему ты опаздываешь к врачу? (Why are you late for your doctor’s appointment?)