How many open syllables are in the word diagnose?

Here's how to figure out the open syllables in "diagnose":

* Open Syllable: A syllable that ends with a vowel sound.

Let's break down the word:

* di-ag-nose

* di- ends with a vowel sound (i) - Open syllable

* ag- ends with a vowel sound (a) - Open syllable

* nose ends with a consonant sound (s) - Closed syllable

Therefore, there are two open syllables in the word "diagnose".