Learn Finnish: Minä rakastan näitä shampoita!

näitä is the partitive plural form of tämä (this). We use the partitive case because the verb rakastaa (to love) always requires its object to be in the partitive. Since you love multiple shampoos, you need the partitive plural.

I remember tätä means 'this' in the partitive. How does it relate to näitä?

You are exactly right! tätä is the partitive singular (this), used for just one thing. näitä is the partitive plural (these), used for multiple things. Since we are talking about shampoos in the plural, we use näitä.

Why does the noun shampoo become shampoita?

The word shampoo is a foreign loanword that ends in two identical vowels (oo). To form the partitive plural for words ending in long vowels, we drop the final vowel and add the plural marker -ita, resulting in shampoita.

Do the pronoun and the noun always have to match cases like this?

Yes! In Finnish, demonstrative pronouns like 'this' or 'these' must agree with the noun they describe. Because the verb makes the shampoos partitive plural (shampoita), the word for 'these' must also be in the partitive plural (näitä).