Mi hermana usa el secador frente al lavabo y luego guarda el peine en un cajón.

My sister uses the hair dryer in front of the sink and then puts the comb away in a drawer.

Breakdown of Mi hermana usa el secador frente al lavabo y luego guarda el peine en un cajón.

• un: a
• en: in
• mi: my
• y: and

Questions & Answers about Mi hermana usa el secador frente al lavabo y luego guarda el peine en un cajón.

Why does Spanish use mi hermana, but then el secador, el peine, and un cajón instead of possessives like su secador and su peine?

This is very common in Spanish. Spanish often uses the definite article (el / la / los / las) where English would use a possessive like his, her, or their, especially when it is already obvious who the object belongs to.

So:

• Mi hermana = my sister
• el secador = the hair dryer
• el peine = the comb

In this sentence, it is natural to assume those objects are the ones your sister is using, so Spanish does not need to repeat possession.

Also:

• un cajón means a drawer, not the drawer, because it is being introduced as an unspecified drawer.

Using su secador or su peine is possible, but it would usually sound more emphatic or only be used when the ownership really matters.

Why is it al lavabo and not a el lavabo?

Because a + el contracts to al in Spanish.

So:

• a + el lavabo → al lavabo

This contraction is mandatory.

Examples:

• Voy al supermercado.
• Miro al niño.
• Frente al espejo.

The only common exception is when el is part of a proper name:

• Voy a El Escorial.

But here lavabo is just a normal noun, so al is required.