Question

sort the words according to the meanings of their shared roots. primarily unicorn primary cornet aerosol postprimary primal anaerobic horn air first

Explanation:

The word "unicorn" has "corn" which relates to "horn", "cornet" also has "corn" related to "horn". "Aerosol" and "anaerobic" have "aer -" related to "air". "Primarily", "primary", "postprimary", "primal" have "prim -" related to "first".

Answer:

horn: unicorn, cornet
air: aerosol, anaerobic
first: primarily, primary, postprimary, primal