Mi hija no quiso tocar la oruga, pero se quedó mirándola un rato.

This is a very common question because both forms come from querer.

• no quiso = preterite
• no quería = imperfect

In this sentence, no quiso tocar la oruga describes a specific reaction at a particular moment: she didn’t want to / wouldn’t touch the caterpillar.

With querer, the preterite often has the sense of a completed decision or refusal:

• No quiso entrar. = He/She wouldn’t go in.
• No quiso tocarla. = He/She wouldn’t touch it.

By contrast, no quería usually describes an ongoing state or general attitude:

• No quería tocar la oruga. = She didn’t want to touch the caterpillar / She wasn’t willing to touch it.

So no quiso fits well if the sentence is telling us what happened in that moment.

Here, quiso is the 3rd person singular preterite of querer.

The subject is mi hija, so:

• yo quise
• tú quisiste
• él/ella quiso

In this context, no quiso tocar often sounds a bit stronger than a simple didn’t want to. It can suggest:

• she didn’t want to
• she refused to
• she wouldn’t

The exact English translation depends on tone and context, but grammatically it is just the preterite of querer.

Because la oruga is a direct object, and Spanish normally does not use the personal a with things or animals unless they are being treated as especially personal, individual, or personified.

So:

• tocar la oruga = correct
• tocar a la oruga = unusual in normal everyday Spanish

The personal a is mainly used with people:

• Veo a mi hermana.
• Conozco a ese profesor.

With an animal like la oruga, Spanish usually leaves out a unless the speaker is treating it almost like a person or a beloved pet.

Using la oruga suggests a specific caterpillar, not just any caterpillar.

Compare:

• tocó una oruga = she touched a caterpillar (one among many, not previously identified)
• tocó la oruga = she touched the caterpillar (a specific one)

In a real situation, the caterpillar is probably visible or already understood from context, so Spanish naturally uses the definite article.

Because pero simply adds contrast, while sino usually corrects a previous negative idea.

Here we have:

• Mi hija no quiso tocar la oruga, pero se quedó mirándola un rato.

This means: She didn’t want to touch it, but she did keep looking at it.

That is a contrast, so pero is the right conjunction.

Use sino in sentences like:

• No tocó la oruga, sino que la observó. = She didn’t touch the caterpillar, but rather observed it.

So:

• pero = but
• sino = but rather / instead

Se quedó comes from quedarse, a very common pronominal verb.

On its own, quedarse can mean things like:

• to stay
• to remain
• to be left
• to end up in a state

In this sentence, se quedó mirándola means something like:

• she stayed looking at it
• she kept staring at it
• she remained watching it

So it does not mean simply she stayed in a place; it means she remained in that activity for some time.

Because the verb here is quedarse, not just quedar.

This is one of those verbs where the pronominal form has its own common meaning:

• quedar can mean to remain, to arrange, to fit, to be located, and more
• quedarse often means to stay, to remain, to keep doing something, or to be left

So in this sentence, se is not reflexive in the literal English sense of herself. It is simply part of the verb quedarse.

That is why you say:

• Se quedó mirándola not
• Quedó mirándola in this context

This is a very useful structure:

quedarse + gerund

It often means:

• to remain doing something
• to keep doing something
• to end up doing something for a while

Examples:

• Se quedó pensando. = He/She stayed thinking.
• Nos quedamos hablando. = We stayed talking.
• Se quedó mirándola. = She stayed looking at it / kept staring at it.

So the sentence has this pattern:

• se quedó = she stayed / remained
• mirándola = looking at it

Together: she stayed looking at it for a while.

Because object pronouns can be attached to a gerund.

The base form is:

• mirando = looking

The direct object pronoun is:

• la = it / her

So:

• mirando + la → mirándola

This is completely normal in Spanish. You also see it with infinitives and affirmative commands:

• verla = to see it/her
• mírala = look at it/her
• mirándola = looking at it/her

Because when the pronoun la is attached to mirando, the normal stress pattern changes, so Spanish adds a written accent to keep the original pronunciation.

Without the pronoun:

• mirando → stress naturally falls on ran

With the pronoun attached:

• mirandola would not show the correct stress clearly by normal spelling rules

So Spanish writes:

• mirándola

This tells you to keep the stress on rán: mi-RÁN-do-la

The same thing happens in forms like:

• diciéndole
• haciéndolo
• leyéndola

It refers to la oruga.

Since oruga is feminine singular, the direct object pronoun is la:

• la oruga → la

So:

• mirándola = looking at it
• literally: looking-at-her/it, but in English for a caterpillar we normally say it

This is a good example of how Spanish grammatical gender affects pronouns.

Yes. Both are correct.

You can say:

• se quedó mirándola
• se quedó mirando la oruga

The difference is mostly one of style and flow.

Using mirándola avoids repeating la oruga, so it sounds smoother because the noun has already been mentioned.

Spanish often prefers a pronoun in this kind of situation, just like English often prefers it instead of repeating the caterpillar.

Un rato means a while.

So:

• se quedó mirándola un rato = she stayed looking at it for a while

It is a very common everyday expression. It usually means an indefinite short or moderate amount of time, depending on context.

Other examples:

• Espera un rato. = Wait a while.
• Estuvimos hablando un rato. = We were talking for a while.

Because Spanish often uses time expressions directly without a preposition where English uses for.

So Spanish says:

• un rato
• dos horas
• toda la tarde

Examples:

• Esperé dos horas. = I waited for two hours.
• Leyó un rato. = He/She read for a while.

That is why se quedó mirándola un rato is perfectly natural without por.

Here it means to touch.

Tocar has several meanings, including:

• to touch
• to play an instrument
• to be someone’s turn
• to concern / affect

In this sentence, because the object is la oruga, the meaning is clearly to touch:

• tocar la oruga = to touch the caterpillar

If it were about music, you might see:

• tocar la guitarra = to play the guitar

Because Spanish normally uses a possessive directly with family nouns in cases like this:

• mi hija = my daughter
• mi madre = my mother
• su hermano = his/her brother

You do not say la mi hija in standard modern Spanish.

So the structure is simply:

• mi
  • hija

This works just like English my daughter.