U pokladny vidím, že moje peněženka není v tašce.

U pokladny means at the checkout / at the cash register.

• u = at, by, near
• pokladna = cash register, checkout

So the phrase sets the scene: At the checkout, I see/realize...

In natural English, this often corresponds to:

• At the checkout
• At the register
• When I’m at the checkout

It does not literally mean that you are somehow “inside” the checkout area; it just means you are by it.

Because the preposition u requires the genitive case.

The dictionary form is:

• pokladna = cash register / checkout

After u, it changes:

• u pokladny = at the checkout

So this is a standard case pattern:

• u domu = by the house
• u stolu = at the table
• u pokladny = at the checkout

A learner should remember: u + genitive.

Literally, yes: vidím means I see.

It is the 1st person singular present tense of vidět (to see):

• vidím = I see

But in this sentence, English would often translate it more naturally as:

• I notice
• I realize
• I see that...

So vidím, že... can mean not only physical seeing, but also becoming aware of something.

že means that and introduces a subordinate clause.

So:

• Vidím, že moje peněženka není v tašce. = I see that my wallet isn’t in the bag.

This is very common in Czech:

• Vím, že... = I know that...
• Myslím, že... = I think that...
• Vidím, že... = I see that...

In English, that is often optional:

• I see my wallet isn’t in the bag
• I see that my wallet isn’t in the bag

In Czech, že is normally expressed here.

Because moje peněženka is the subject of the clause moje peněženka není v tašce.

That clause means:

• my wallet is not in the bag

Here:

• peněženka is in the nominative case because it is the subject
• moje agrees with peněženka

So:

• moje peněženka = my wallet (subject form)

If the wallet were a direct object, then you might see a different case:

• Nemůžu najít moji/mojí peněženku. = I can’t find my wallet.

But in your sentence, the wallet is not something you are acting on inside the subordinate clause; it is simply the thing that is not in the bag.

In Czech, negation is usually built directly into the verb with ne-.

• je = is
• není = is not

So:

• moje peněženka je v tašce = my wallet is in the bag
• moje peněženka není v tašce = my wallet is not in the bag

This is very normal in Czech:

• mám = I have

• nemám = I don’t have

• rozumím = I understand
• nerozumím = I don’t understand

So Czech often negates the verb itself rather than using a separate word like English not.

Because v meaning in takes the locative case when it expresses location.

• taška = bag
• v tašce = in the bag

So here:

• v = in
• tašce = locative singular of taška

This is a very important pattern:

• v domě = in the house
• v práci = at work / in work
• v tašce = in the bag

Be careful: v can also take the accusative when it means movement into, but not here.

Compare:

• je v tašce = it is in the bag (location → locative)
• dám to do tašky = I’ll put it into the bag

Here is the full breakdown:

• U pokladny

  • u
    • genitive
  • pokladny = genitive singular

• vidím

  • verb, 1st person singular present

• že

  • conjunction = that

• moje peněženka

  • nominative
  • subject of the subordinate clause

• není

  • verb to be, 3rd person singular present, negative

• v tašce

  • v
    • locative for location
  • tašce = locative singular

So this one sentence gives you three useful structures at once:

• u + genitive
• subject in nominative
• v + locative for location

The given word order is natural and clear:

• U pokladny vidím, že moje peněženka není v tašce.

But Czech word order is more flexible than English, because cases show the grammatical relationships.

Possible variations include:

• Vidím u pokladny, že moje peněženka není v tašce.
• Moje peněženka není v tašce, vidím u pokladny.
  This is possible, but much less natural in ordinary speech.

The original sentence is good because it presents the situation in a natural order:

1. where you are → U pokladny
2. what you realize → vidím
3. what the realization is → že moje peněženka není v tašce

So yes, the word order can change, but not every version sounds equally natural.

Yes. Depending on nuance, Czech speakers might also say:

• zjišťuji, že... = I find out / I discover that...
• uvědomím si, že... = I realize that...
• vidím, že... = I see / I notice that...

Your sentence with vidím is understandable and natural, especially if the emphasis is on the moment of noticing. But in some contexts, English I realize might correspond more closely to:

• U pokladny si uvědomím, že moje peněženka není v tašce.

Still, for a learner, vidím, že... is a very useful and common structure.

Taška is a fairly general word for bag.

Depending on context, it could mean:

• a shopping bag
• a tote bag
• a school bag
• a larger handbag

If you specifically mean a woman’s purse/handbag, Czech often uses:

• kabelka

So:

• peněženka = wallet
• taška = bag
• kabelka = handbag/purse

In your sentence, taška is perfectly fine if the intended meaning is simply bag.

This is a useful vocabulary point because English varies by region.

In Czech:

• peněženka = wallet

It means the item used to hold money, cards, ID, etc.

In English:

• American English usually says wallet
• British English may use wallet for men and sometimes purse for a small money-holder, especially for women

But Czech peněženka is not the larger handbag. That would be kabelka.

So in this sentence, peněženka is definitely wallet, not bag.

A natural spoken rhythm would often stress the important new information, especially the problem:

U pokladny vidím, že moje peněženka není v tašce.

Likely emphasis:

• U pokladny if you want to highlight the moment/place
• peněženka if that is the key item
• není v tašce if the important point is that it’s missing

For example, if you are telling a story, the strong information is often:

• není v tašce = is not in the bag

Czech stress within individual words is regularly on the first syllable, but sentence-level emphasis depends on what you want to highlight.

Sometimes yes, but it changes the feel slightly.

• že moje peněženka není v tašce = that my wallet isn’t in the bag
• že peněženka není v tašce = that the wallet isn’t in the bag

Czech often omits possessives when ownership is obvious from context, but keeping moje is very natural here because:

• it makes the sentence explicit
• it sounds normal in a moment of personal realization
• it avoids any ambiguity about whose wallet is meant

So omitting it is possible in some contexts, but the full version with moje is absolutely fine and often preferable for learners.