Ta plama jest nowa.

Because ta is the feminine singular form of this.

In Polish, demonstratives must agree with the noun in gender, number, and case:

• ten = masculine
• ta = feminine
• to = neuter

Since plama is a feminine noun, you say ta plama.

Examples:

• ten dom = this house
• ta książka = this book
• to okno = this window

A very common clue is the ending -a in the dictionary form of a noun. Many Polish nouns ending in -a are feminine, and plama is one of them.

So:

• plama = a feminine noun
• therefore it takes feminine forms like ta and nowa

Be careful, though: not every noun ending in -a is feminine, but it is a very useful rule of thumb for beginners.

Because adjectives in Polish must agree with the noun they describe.

Since plama is:

• feminine
• singular
• nominative here

the adjective must also be:

• feminine
• singular
• nominative

So:

• masculine: nowy
• feminine: nowa
• neuter: nowe

Examples:

• nowy samochód = a new car
• nowa plama = a new stain
• nowe okno = a new window

Jest is the 3rd person singular present tense of the verb być = to be.

So:

• jestem = I am
• jesteś = you are
• jest = he/she/it is

In Ta plama jest nowa, jest means is.

It links the subject ta plama with the adjective nowa, just like English is in This stain is new.

In normal standard Polish, no — you usually keep jest in sentences like this.

So:

• Ta plama jest nowa. = correct
• Ta plama nowa. = not standard Polish

Polish generally requires the present-tense form of być in this kind of sentence.

Because here plama is the subject of the sentence, so it is in the nominative case, which is the dictionary form.

The sentence structure is:

• Ta plama = the subject
• jest nowa = what is being said about the subject

Since the noun is the subject, it stays as plama.

The most neutral word order is:

Ta plama jest nowa.

Polish word order is more flexible than English, though, because endings carry a lot of grammatical information.

You may also hear variations such as:

• Nowa jest ta plama.
• Ta nowa jest plama. — much less natural in most contexts

Different word orders can change emphasis rather than basic meaning. For a learner, the safest version is the original one: Ta plama jest nowa.

Normally ta plama means this stain.

Polish usually contrasts:

• ta = this
• tamta = that

So:

• ta plama = this stain
• tamta plama = that stain

In real conversation, context can sometimes blur the difference a little, but the basic meaning of ta is this.

A rough pronunciation is PLA-ma.

A few tips:

• pl is pronounced clearly, like in English play, but without adding an extra vowel
• a is a simple ah sound
• stress in Polish usually falls on the second-to-last syllable, so here the stress is on PLA

So: PLA-ma

A rough English-style guide is:

ta PLA-ma yest NO-va

A few pronunciation notes:

• ta = tah
• plama = PLA-ma
• jest starts with a y-like sound: yest
• w in Polish sounds like English v, so nowa sounds like NO-va
• stress is usually on the second-to-last syllable:
  • PLA-ma
  • NO-va

So the full rhythm is:

ta PLA-ma yest NO-va