Я п’ю чай чашкою.

Because Ukrainian often uses the instrumental case by itself where English would use with. The case ending already shows the idea of means or instrument.

For example:

• пишу ручкою = I write with a pen
• їм ложкою = I eat with a spoon

So чашкою can express with a cup / using a cup without a separate preposition.

Literally, it means with / using a cup. That is what the instrumental case most directly expresses here.

If you specifically want to say from a cup, Ukrainian more naturally uses:

• з чашки
• із чашки

And у чашці means in a cup, which is a different idea. So this sentence is grammatical, but if the idea is simply drinking tea from a cup, many speakers would prefer Я п’ю чай з чашки.

Чай is the direct object, so it is in the accusative case. But чай is a masculine inanimate noun, and in the singular, that type of noun often has the same form in the nominative and accusative.

So:

• nominative: чай
• accusative: чай

That is why you do not see a visible change.

Yes, but the nuance is a little different. П’ю чай is the basic, neutral way to say it. П’ю чаю uses the genitive and can suggest some tea or an indefinite amount.

This kind of genitive is especially common in phrases like випити чаю. For a beginner, though, п’ю чай is the safest and most straightforward form.

Because Ukrainian verbs often change their stem when they are conjugated. The infinitive is пити, but the 1st person singular present form is п’ю.

This is the normal present-tense pattern:

• я п’ю
• ти п’єш
• він/вона п’є

So this is something you learn as part of the verb’s conjugation.

The apostrophe shows that п stays hard and is not softened by the following ю. It also signals that ю is pronounced like yu.

So п’ю is pronounced roughly like p-yoo, not like a softened pyu with one blended sound. The apostrophe is very common after labial consonants such as б, п, в, м, ф before я, ю, є, ї.

Yes. Ukrainian often leaves out subject pronouns because the verb ending already tells you the person. П’ю already means I drink / I am drinking.

So П’ю чай чашкою is possible. Keeping я adds emphasis, contrast, or clarity.

Yes. Ukrainian word order is fairly flexible because case endings help show who is doing what. Changing the order usually changes emphasis, not the basic meaning.

For example:

• Я п’ю чай чашкою = straightforward textbook-style order
• Чашкою я п’ю чай = stronger focus on the cup
• Чай я п’ю чашкою = stronger focus on tea

Not every order sounds equally natural in every situation, but reordering is very common in Ukrainian.

Ukrainian has no articles. It does not have direct equivalents of a and the.

So:

• чай can mean tea or the tea
• чашкою can mean with a cup or with the cup

Context tells you which meaning is intended.