Essa criança quer comer um sanduíche de salada e queijo.

In standard Portuguese, esta means this (near the speaker) and essa means that (near the listener, or something already mentioned).

However, in everyday Brazilian Portuguese, people often use esse/essa where English would say either this or that. So essa criança can sound very natural in Brazil, even in situations where an English speaker might expect this child.

So:

• standard grammar: esta = this, essa = that
• common Brazilian usage: essa is often used much more broadly

Because criança is a grammatically feminine noun in Portuguese. The demonstrative has to agree with the noun, not with the real-life sex of the person.

So you say:

• essa criança = this/that child

Even if the child is male, criança still takes feminine agreement because the word itself is feminine.

If you want a clearly masculine word, you might use:

• esse menino = this/that boy

Because essa already works as the determiner. It fills the same slot that an article like a or uma would fill.

Compare:

• a criança = the child
• uma criança = a child
• essa criança = this/that child

So you do not say uma essa criança here.

Quer is the third-person singular form of the verb querer (to want).

The subject is essa criança = this/that child, which matches he/she/it in English grammar terms. So the verb must be:

• eu quero = I want
• você/ele/ela quer = you/he/she wants
• nós queremos = we want

That is why the sentence uses quer.

Because in Portuguese, after many verbs, the second verb goes directly in the infinitive.

So:

• quer comer = wants to eat
• vai sair = is going to leave / is going out
• precisa estudar = needs to study

English usually uses to before the second verb, but Portuguese often does not.

Because sanduíche is a masculine noun in Portuguese, so it takes um.

Even though the word ends in -e, that does not automatically tell you the gender. Portuguese nouns ending in -e can be masculine or feminine, and you usually have to learn them individually.

So:

• um sanduíche = a sandwich

Portuguese often uses de to describe the type, flavor, or filling of food.

So:

• sanduíche de queijo = cheese sandwich
• pizza de frango = chicken pizza
• suco de laranja = orange juice

Literally, de often looks like of, but in natural English it is often translated as with, made of, or just turned into a noun modifier:

• sanduíche de salada e queijo ≈ salad and cheese sandwich

Because one de can govern both nouns in the list.

So:

• de salada e queijo = of salad and cheese

This is normal and natural. Portuguese does not need to repeat the preposition before each item unless there is a special reason to do so.

Compare:

• sanduíche de salada e queijo = a salad-and-cheese sandwich

Because in food descriptions, Portuguese often leaves out articles when naming ingredients in a general way.

So these are natural:

• sanduíche de queijo
• pizza de frango
• suco de laranja

Adding articles like da salada or do queijo would usually sound more specific and less like a normal food label.

In criança, the ç makes an s sound. It is used before a, o, u to keep that s sound.

So:

• ç = s sound

A rough English-friendly pronunciation of criança is:

• kree-AHN-sa

A few important points:

• the stress is on AN
• ç sounds like s
• ã is nasal, so the ahn sound is nasalized rather than fully open like English ah

A rough Brazilian pronunciation is:

• sahn-DWEE-shee

The accent mark in sanduíche shows where the stress goes: the stressed part is uí.

A few pronunciation notes:

• san is nasalized a bit in Brazilian Portuguese
• uí is the stressed part
• ch in Portuguese sounds like English sh

The plural is:

• sanduíches = sandwiches

So:

• um sanduíche
• dois sanduíches