Graded and ungraded adjectives
Pattern 21: how ADJ it v-link to-inf
The adjective follows how and is followed by introductory it, a link verb, and a to-infinitive clause. The to-infinitive clause refers to the action that is being commented on.
I can't emphasize how difficult it is to get supplies there.
How hard it is to be patient.
Sometimes the to-infinitive clause comes directly after the adjective. this pattern is how ADJ to-inf.
How comforting to be hidden from danger.