Když jsem byl malý, neměl jsem rád rýži, ale teď ji jím často s rajčetem a okurkou.

Here když means when.

So Když jsem byl malý = When I was little / When I was young.

A useful extra note: když can sometimes also mean if in other contexts, but in this sentence it clearly means when.

Because Když jsem byl malý is a subordinate clause, and Czech normally separates subordinate clauses with a comma.

So the structure is:

• Když jsem byl malý, = subordinate clause
• neměl jsem rád rýži... = main clause

This is very similar to English When I was little, ...

This is how the Czech past tense is built.

Czech past tense usually has:

• a past participle: byl, měl, jedl, etc.
• plus an auxiliary form of být: jsem, jsi, jsme, etc.

So:

• jsem byl = I was
• jsem neměl = I did not have
• literally, Czech past tense often looks a bit like I am been / I am had, though of course you should not translate it that way.

In real Czech word order, the auxiliary often comes second in the clause, so you get:

• Když jsem byl malý
• neměl jsem rád

Yes. Both byl and malý agree with the speaker’s gender.

If a man is speaking:

• Když jsem byl malý = When I was little

If a woman is speaking:

• Když jsem byla malá

And the rest of the sentence would also change where needed:

• neměla jsem ráda rýži instead of
• neměl jsem rád rýži

So this sentence, as written, sounds like it is spoken by a male speaker.

Czech very often expresses to like with mít rád or mít ráda, literally to have liked / to have dear.

So:

• mám rád rýži = I like rice (male speaker)
• neměl jsem rád rýži = I didn’t like rice

This is one of the most common ways to talk about liking things in Czech.

A female speaker would say:

• mám ráda
• neměla jsem ráda

Rád is an adjective-like word used in expressions such as mít rád.

It agrees with the subject:

• male speaker: rád
• female speaker: ráda
• plural masculine personal: rádi
• plural non-masculine personal: rády

So in this sentence:

• neměl jsem rád rýži = male speaker
• a female speaker would say neměla jsem ráda rýži

This agreement is very important and is a common thing learners notice early.

Because rýže is in the accusative case here.

The verb phrase mít rád takes a direct object, and direct objects are often in the accusative.

So:

• nominative: rýže = rice
• accusative: rýži

That is why the sentence has:

• neměl jsem rád rýži

Because Czech usually does not need subject pronouns when the verb already shows who the subject is.

For example:

• jsem byl already tells you it is I
• neměl jsem also tells you it is I
• jím also tells you it is I eat

So já is often omitted unless you want emphasis or contrast.

Czech does this much more than English.

Ji means it, and it refers back to rýži.

So instead of repeating rýži, Czech uses the pronoun:

• teď ji jím často = now I eat it often

Because rýže is a feminine noun, the accusative pronoun is ji.

This is a very natural way to avoid repetition.

Because ji is a short unstressed pronoun, and these pronouns usually go very early in the clause, often in the second position area.

So:

• ale teď ji jím často

sounds natural.

Czech short pronouns such as mi, ti, ho, ji, se, si tend to cluster near the beginning of the clause rather than staying where English would put them.

So even though English says I eat it often, Czech prefers teď ji jím často rather than teď jím ji často.

Jím is the 1st person singular present form of the verb jíst = to eat.

So:

• jíst = to eat
• jím = I eat
• jíš = you eat
• jí = he/she eats
• jíme = we eat
• jíte = you eat
• jedí = they eat

This verb is a bit irregular, so it is very normal that learners stop and ask about jím.

Because it describes a present habit:

• teď = now
• jím často = I eat it often

So the contrast is:

• When I was little, I didn’t like rice
• but now I eat it often

This is a nice example of Czech using past tense for the earlier state and present tense for the current habit, just like English.

Because the preposition s in the sense of with takes the instrumental case.

So the nouns after s must change:

• rajče → rajčetem
• okurka → okurkou

That is why the sentence says:

• s rajčetem a okurkou = with tomato and cucumber

Because the nouns belong to different genders and declension patterns.

• rajče is a neuter noun, so in the instrumental singular it becomes rajčetem
• okurka is a feminine noun, so in the instrumental singular it becomes okurkou

So both are in the same case, but they take different endings because they are different kinds of nouns.

Yes, they could be plural, but singular is also perfectly natural.

The sentence gives the idea of eating rice with tomato and cucumber as ingredients or accompaniment. Czech often uses singular nouns this way.

If you wanted plural, you could say something like:

• s rajčaty a okurkami = with tomatoes and cucumbers

Both are possible, depending on what exactly you want to say.

Not exactly. A female speaker would normally change the gendered forms.

The female version would be:

Když jsem byla malá, neměla jsem ráda rýži, ale teď ji jím často s rajčetem a okurkou.

The part ji jím často stays the same, but these parts change:

• byl malý → byla malá
• neměl jsem rád → neměla jsem ráda

So the written sentence as given is specifically a male speaker’s version.