fiddle around, also UK: fiddle aboutvi phrasalphrasal verb, intransitive: Verb with adverb(s) or preposition(s), having special meaning and not taking direct object--for example, "make up" [=reconcile]: "After they fought, they made up."
informal (waste time doing [sth] trivial)
闲荡，虚度时光 xián dàng，xū dù shí guāng
He began to fiddle around doing crossword puzzles, but soon noticed his English was improving.
fiddle around with [sth], also UK: fiddle about with [sth]vi phrasal + prep
informal (play absent-mindedly with)
She fiddled around with the things on her desk while I was talking.
play second fiddle to [sb]v exprverbal expression: Phrase with special meaning functioning as verb--for example, "put their heads together," "come to an end."
figurative (be considered less important)
当副手，位于次要地位 dāng fù shǒu，wèi yú cì yào dì wèi
She always played second fiddle to her talented older sister.
second fiddlennoun: Refers to person, place, thing, quality, etc.
figurative (less important status) (音乐)
第二小提琴部 dì èr xiǎo tí qín bù
次要地位 cì yào dì wèi
The Vice President will always play second fiddle to the President.