Final answer:
Kindergarten teachers should select vocabulary words that appear multiple times in texts for their read-alouds, to provide repeated exposure and aid vocabulary learning.
Step-by-step explanation:
When a kindergarten teacher prepares to use an interactive read-aloud to enhance students' vocabulary knowledge, the guideline that should be adhered to when selecting vocabulary words is that those words should be used multiple times. This is because repeated exposure in a meaningful context helps students learn new vocabulary effectively. Words that are abstract in meaning should generally be avoided at this level as they can be challenging for young learners to conceptualize. Teachers should also aim to select words that are relevant to the students' experiences and which they are likely to encounter again in other texts, rather than words unique to an individual text which they may not see elsewhere.