The Hebrew alphabet is an "abjad" and so only the consonants are written, and readers must supply the vowels. Since that can be difficult, the vowels can be marked as dots called “nikkud” or “tnuah” (plural ”nikkud” signs and “tnuot” respectively.) In Modern Hebrew, some letters can denote vowels, which are called "matres lectionis" (mothers of the reading) since they greatly help reading. Vav (or Waw) can make the 'oo' sound (/u/ in IPA) like in food. Yodh (or Yud) can make the 'ee' sound (/i/ in IPA) like in feed.