Learn Spanish (Latin America): Ese hombre es guapo, guapísimo.

To add the -ísimo suffix to an adjective ending in a vowel, you first drop that final vowel. So, guapo becomes guap-, and then we add -ísimo to get guapísimo. Because it describes ese hombre (a masculine noun), the suffix ends in -o.

Is guapísimo exactly the same as saying muy guapo?

They are very similar, but -ísimo is usually stronger! While muy guapo means "very handsome," guapísimo is more like "extremely handsome" or "gorgeous." It is a great way to add extra emotion or emphasis to your sentence.

Why does guapísimo have an accent mark on the "i", but guapo does not?

The suffix -ísimo always has a written accent mark on the first í. This is because it forces the spoken stress (the loudest part of the word) onto that syllable (gua-pí-si-mo). In Spanish, words with the stress on the third-to-last syllable always get a written accent mark.

Why does the sentence use ese instead of eso for "that"?