You might be able to get the text-to-speech option on your phone to do this for you, since it involves saying the fractions aloud.
1/2 ⇒ one-half
2/3 ⇒ two thirds
1/4 ⇒ one quarter, or one fourth
2/4 ⇒ two fourths, or two quarters
2/5 ⇒ two fifths
5/6 ⇒ five sixths
4/7 ⇒ four sevenths
6/8 ⇒ six eighths
5/11 ⇒ five elevenths
1/12 ⇒ one-twelfth
1/20 ⇒ one-twentieth
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IMO, the use of a hyphen or not depends on the context. If the fraction itself is the focus, you might say one twelfth. If it is describing a portion of something else, you might say one-twelfth [of a cake].