1. 無論用作介詞還是用作副詞,均可表示動態(tài)意義或靜態(tài)意義: (1) 表示動態(tài)意義,意為“橫過”“到…的另一邊”。如: Can you swim across? 你能游過去嗎? (副詞用法) I cam swim across the river in 10 minutes. 我可以在10分鐘之內(nèi)游過河去。(介詞用法) (2) 表示靜態(tài)意義,意為“在…的另一邊”。如: My house is just across the street. 我家就在街道對面。(介詞用法) We leave Dover at ten and we should be across in France by midnight. 我們10點(diǎn)鐘離開多佛,午夜時應(yīng)能抵達(dá)法國那邊。(副詞用法) 2. across from與from across都可以說,但含義稍有區(qū)別: (1) across from 表靜態(tài)意義,意為“在對面”,與opposite同義,此時也可省略from只說across。如: Just across from our house there's a school. 就在我們房子的對面有一所學(xué)校。 I'm staying at a little hotel just across from the Libyan Embassy. 我住在利比亞大使館正對面的一所小旅館里。 (2) from across 則表動態(tài)意義,意為“從……的對面”。如: He shouted to me from across the room. 他從房間的另一邊向我喊。 They waved at us from across the room. 他們從房間那一頭向我們招手。 3. 注意不要與動詞cross弄混: (1) 表示“穿過”時的用法比較: It's dangerous for an old man to cross such a crowded street. 老人穿過這樣擁擠的街道很危險。 It's dangerous for an old man to walk across such a crowded street. 老人穿過這樣擁擠的街道很危險。 (2) 表示“交叉”時的用法比較: The roads cross just outside the village. 那兩條路就在村外交叉。 He sat there with his arms across his chest. 他坐在那兒,兩臂交叉放在胸前。(介詞用法) 4. 用于習(xí)語come across,主要用法有: (1) 偶然遇見,碰見(=run across) Where did you come [run] across her? 你在那兒碰到她的? I've just come across a beautiful poem in this book. 我在這本書里偶然發(fā)現(xiàn)一首優(yōu)美的詩。 (2) 被理解,被傳達(dá)(=come over) He spoke for a long time but his meaning did not really come across. 他講了很長時間,但他的意思沒有人真正理解。 (3) 使人產(chǎn)生某種印象(=come over) Your speech came across very well. 你的演說相當(dāng)受歡迎。 He came across as sympathetic / a sympathetic person. 他給人以有同情心的印象。 注意以下用法,它不是習(xí)語,其中的across為副詞,表示“在另一邊”: Come across to my office this afternoon. 你今天下午到我辦公室來一趟。