An analogy usually has 4 parts, 1 of which is what you need to supply.
What are the first 2 parts you've been given?
?? : ?? = thorn : ??
Answers.com - Complete analogies using the word that begins with ...
Thorns analogy for thorns starting with scr spr str thr? Analogy for thorn that beings with scr spr str thr? Analogie for downpour beginning with scr spr ...
Answers.com - Glue is to stick as thorn is to
Analogy question: Glue is to stick as thorn is to? scratch. ...
what is the analogies for grieve