Learn Hardcore Ukrainian: Я взяв чек і поклав його в сумку. - I took the receipt and put it into the bag.

взяв = took (from perfective взяти/узяти)
поклав = put/laid (from perfective покласти) Perfective shows completed, one-time actions (took → then put). The -в ending here also signals masculine gender of the subject in the past tense.

How would a female speaker or a group say it?

Female: Я взяла чек і поклала його в сумку.
Plural: Ми взяли чек і поклали його в сумку. If the object is plural, change the pronoun too: Ми взяли чеки і поклали їх у сумку.

Why not use брав or клав instead of взяв and поклав?

Брав/клав are imperfective past forms, which suggest an ongoing, repeated, or background action (was taking/was putting, used to take/put). The perfective взяв/поклав presents a finished sequence: took it, then put it in.

What are the infinitives and future forms of these verbs?

Take: infinitive взяти/узяти (both standard). Future: я візьму, ти візьмеш, …
Put (lay): infinitive покласти. Future: я покладу, ти покладеш, … Imperfective partners (for ongoing/habitual meaning): брати (present: беру), класти (present: кладу).

What does його mean here, and why not нього?

Here його means “it” (referring to the masculine inanimate noun чек). Use його for a direct object without a preposition. After any preposition, Ukrainian switches to n-forms: нього/ньому/ним (e.g., на нього, до нього). So in this sentence його is correct; нього would only appear if a preposition directly preceded it.

Could його here mean “his” instead of “it”?

It could in other contexts, because його is also the possessive “his.” Position and function disambiguate it:

As a possessive: його чек = his receipt.
As a pronoun object (our sentence): поклав його = put it/him. Context makes it clear that it refers to the receipt (it).

Can I leave out його and just say “Я взяв чек і поклав в сумку”?

You can, and people often do when the object is obvious from context. Including його is slightly clearer and more typical in careful speech, but omitting it here is acceptable and natural.

Why is it в сумку and not в сумці?

Because it’s motion into a place. Ukrainian uses:

Accusative for direction/into: в сумку (into the bag).
Locative for location/in: в сумці (in the bag). So “put into” needs the accusative сумку.

Should it be в or у before сумку?

Both are correct; в/у alternate for euphony. Choose what sounds smoother. Many speakers prefer у сумку here to avoid the consonant cluster in в сумку, but в сумку is also very common.

Can I move the pronoun around, like поклав в сумку його?

Yes, Ukrainian word order is flexible. The most neutral is поклав його в сумку. Moving the pronoun to the end (поклав в сумку його) can add emphasis to “it,” but sounds a bit marked. Fronting the prepositional phrase (в сумку поклав його) emphasizes the destination.

Is положив acceptable instead of поклав?

In colloquial speech you’ll hear положив, but in the standard language поклав (from покласти) is preferred. If you want to sound standard/neutral, use поклав.

What about поставив—can I use that?

Use поставив when you “set/stand” something upright. Поклав is for laying something down or putting it inside (like into a bag). So for a receipt into a bag, поклав is the natural choice.

Why isn’t it чека (with -а) after взяв?

Masculine inanimate nouns in the accusative singular keep the nominative form: чек. The -а ending (genitive/accusative of animate) is used for masculine animate nouns. So:

Inanimate: взяв чек.
Animate: взяв брата.

How do I pronounce the sentence?

Rough guide: Ya vzyáv chek i pokláv yoho v súmku.

Stress: взяв, поклав, його, сумку.
Note: Ukrainian г is a voiced h [ɦ] in його; в is a light w-like sound [ʋ]. Many prefer у сумку because it flows more smoothly.

Does чек always mean “receipt”? What about “bill” or “invoice”?

Чек most commonly means a (sales) receipt.
“Bill/check (at a restaurant)” is рахунок.
An official receipt/acknowledgment can be квитанція. A bank “cheque” also uses чек (e.g., банківський чек), but that’s less common in everyday speech.

Can I say узяв instead of взяв?

Yes. Взяти and узяти are both standard; speakers choose based on euphony. In this sentence, Я узяв чек і поклав його в/у сумку is perfectly fine.