In Skyrim, the player character can use powerful magic shouts (Thu'ums) to achieve their goals. Every shout consists of three words, however, the player can use the first one or two words to achieve the same effect with less power but at a shorter cooldown.
Given a lowercase ASCII Thu'um phrase without punctuation or spaces, return how many words of power it contains.
fusrodah -> 3 dur -> 1 kaandrem -> 2 odah -> 2 vengaarnos -> 3
The input will always be a lowercase ASCII string formed by taking one of the shouts below, choosing the first 1, 2, or 3 words from that shout, and concatenating the words in order.
dur neh viir faas ru maar feim zii gron fo krah diin fus ro dah gaan lah haas gol hah dov hun kaal zoor iiz slen nus joor zah frul kaan drem ov krii lun aus laas yah nir lok vah koor mid vur shaan mul qah diiv od ah viing raan mir tah rii vaaz zol strun bah qo su grah dun tiid klo ul ven gaar nos wuld nah kest yol toor shul zul mey gut zun haal viik
fusrodah are all valid inputs, but
fusroviir isn't because it uses words from mixed shouts, and
rodah isn't because it's not a prefix of a shout. You also don't have to handle the empty string input.
Shortest code in bytes wins.