C2 giving all your attention to something全神貫注的;專心致志的
She was so engrossed by/in the book that she forgot the cookies in the oven.她看書看得太入迷了,以至於忘了烤箱中正烤着餅幹。
They were so engrossed in/with what they were doing that they didn't hear me come in.他們專心致志地做着手頭的事,連我進去都沒有聽見。