Pekmez je bio toliko ljepljiv da sam morala oprati ruke dvaput.

Because je bio is the past tense of biti (to be) in the masculine singular.

• je = is/was (3rd person singular auxiliary)
• bio = past participle been/was

Together, je bio means was.

Since pekmez is a masculine noun, the participle is bio.
If the subject were feminine, it would be bila; if neuter, bilo.

Because ljepljiv must agree with pekmez in gender and number.

Pekmez is grammatically masculine singular, so the adjective also appears in masculine singular:

• bio ljepljiv = masculine singular
• bila ljepljiva = feminine singular
• bilo ljepljivo = neuter singular

In Croatian, adjectives agree with the noun they describe.

This is a very common Croatian structure meaning so ... that ...

• toliko ljepljiv = so sticky
• da sam morala oprati ruke dvaput = that I had to wash my hands twice

So:

• toliko ... da ... = so ... that ...

You can use it with many adjectives:

• Bio je toliko umoran da je odmah zaspao. = He was so tired that he fell asleep immediately.
• Bilo je toliko hladno da nismo izašli. = It was so cold that we didn’t go out.

Sam is the 1st person singular auxiliary verb used to make the past tense.

Croatian past tense is often formed with:

• auxiliary biti in the present tense
• plus a past participle

So:

• sam morala = I had to / I was forced to
• literally: I am had-to, but in real English this becomes simple past

Here the speaker is female, so it is morala. A male speaker would say:

• da sam morao oprati ruke dvaput

Yes. Morala shows that the speaker is female.

In Croatian, past participles usually agree with the gender of the subject:

• ja sam morao = I had to (male speaker)
• ja sam morala = I had to (female speaker)

So from this sentence, you can tell the person speaking is a woman.

Because Croatian auxiliary forms like sam, si, je, smo, ste, su are clitics, and clitics tend to appear in the second position in the clause.

So after da, the clitic sam comes early:

• da sam morala oprati ruke dvaput

Not:

• da morala sam oprati ruke dvaput (unnatural here)

This word-order rule is very important in Croatian.

Because oprati is the perfective verb, while prati is imperfective.

• prati = to wash, to be washing, washing in general
• oprati = to wash completely / to wash off / to finish washing

After morati (to have to), Croatian often uses the infinitive of the action that had to be completed. Here the meaning is a completed action:

• she had to wash her hands, and she did it

So oprati fits better than prati.

Because oprati takes a direct object, and ruke here is in the accusative plural.

The noun is:

• nominative singular: ruka = hand
• nominative plural: ruke = hands
• accusative plural: ruke = hands

For this noun, nominative plural and accusative plural look the same.

So:

• oprati ruke = to wash one’s hands

Because Croatian often omits possessive words like my, your, his, etc. when they are obvious from context, especially with body parts.

So:

• oprati ruke naturally means wash my/the hands, and in context it is understood as my hands

You could say:

• oprati svoje ruke

but that usually sounds unnecessary here unless you want emphasis or contrast.

This is different from English, where wash my hands is more normal than wash hands.

Dvaput means twice.

Yes, it is basically the same in meaning as dva puta.

Both are common:

• dvaput = twice
• dva puta = two times / twice

Dvaput is a bit more compact and often feels slightly more fixed as an adverb, like English twice.

You may also see:

• triput = three times
• tri puta = three times

Yes, ljepljiv means sticky.

It can describe things like jam, honey, tape, hands, surfaces, and so on:

• ljepljive ruke = sticky hands
• ljepljiva masa = a sticky mass
• stol je ljepljiv = the table is sticky

Here it agrees with pekmez:

• ljepljiv = masculine singular

Pekmez is a type of fruit preserve, usually a thick jam-like spread. In the Balkans it often refers especially to a dense fruit preserve, traditionally made from plums, though it can be made from other fruits too.

For grammar, the important thing is that pekmez is masculine singular, which is why the sentence uses:

• je bio
• ljepljiv

Yes, Croatian word order is flexible, but not completely free.

The given sentence is very natural:

• Pekmez je bio toliko ljepljiv da sam morala oprati ruke dvaput.

You might also hear emphasis changes such as:

• Toliko je pekmez bio ljepljiv da sam morala oprati ruke dvaput.
• Morala sam oprati ruke dvaput jer je pekmez bio toliko ljepljiv.

But the original is the most neutral and straightforward version.

Because Croatian has no articles like English a, an, the.

So:

• pekmez can mean jam, the jam, or some jam, depending on context
• ruke can mean hands or the hands, again depending on context

Croatian speakers understand definiteness from the situation, word order, and context rather than from articles.

Usually had to wash is the best natural translation here.

The prefix o- in oprati often suggests completing the washing or washing something off, but in many everyday sentences it simply gives the perfective sense of wash completely.

So:

• morala oprati ruke = had to wash my hands

That is the most natural English version, even though the Croatian verb is perfective.