Household

¡Hay un oso en la cocina!
Hay means there is or there are. It never changes form.
¡Hay un oso en la cocina!
There is a bear in the kitchen!
Hay dos ventanas pequeñas en el baño.
There are two small windows in the bathroom.
Gender
Nouns ending in ‑o are usually masculine, and nouns ending in ‑a are usually feminine.
But what about words that end in consonants? Luckily, most of them are still predictable!
masculinefeminine
el hospitalla pared
el tenedorla habitación
la televisión
la costumbre
la luz
However, languages and days of the week are always masculine, no matter what letter they end with.
el español
Spanish
el inglés
English
el lunes
Monday
el sábado
Saturday
Ese vs. esa
In Spanish, the word for that changes depending on the gender of the noun it goes with.
ese dormitorio
that bedroom​
esa nevera
that fridge​
The word for those changes depending on gender as well.
esos baños
those bathrooms​
esas camisas
those shirts​