suck up vs soak up

suck up and soak up both are verbs.

Word	Noun	Adjective	Verb	Adverb
suck up	No	No	Yes	No
soak up	No	No	Yes	No

As verbs, suck up and soak up are synonyms defined as:

Other synonyms of suck up include absorb, draw, imbibe, sop up, suck, take in, take up.

suck up (verb)	soak up (verb)
try to gain favor by cringing or flattering	devote (oneself) fully to
take in, also metaphorically	take in, also metaphorically
ingratiate oneself to; often with insincere behavior