Question

is there another way of saying better understand? the snetence im trying to write is "imagery can also help the reader to better understand the poem thus the reader is able to ...(is it appropriate to write better understand again here?)"

Answer 1

Try reversing the words and using synonyms, and then rephrasing.
... to understand ... better
... to comprehend ...
... to get the author's message ...
(And any others you can think of)