Third-person singular simple present indicative form of stage.(verb)
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Use "stages" in a sentence
"This might proceed in stages from the in vitro biosynthesis of better and more efficient enzymes, to the biosynthesis of the corresponding nucleic acid molecules, and to the introduction of these molecules into the genome of organisms, whether via injection, viral introduction into germ cells, or via"
"As for quality, I guess what they call the stages of sleep really matters."
"Last year I made a house and put the house together in stages (e.g. one wall to one wall, wait to let it dry, then attach those walls to another, wait to let it dry, etc.)"