【正文】
9個(gè)月,而他已經(jīng)能站起來(lái)了?! ≡诂F(xiàn)在時(shí)和一般過(guò)去時(shí)中,can/could與 be able to通??梢曰Q,be able to往往用于表示學(xué)到的技能: I tried again and found I could swim/was able to swim. 我再次努力,就發(fā)現(xiàn)自己會(huì)游泳了?! ≡谡劦秸f(shuō)話時(shí)正在發(fā)生的事時(shí),一般不用 be able to: Look! I can stand on my head. 看!我能倒立?! ≡诒硎境晒Φ赝瓿赡骋痪唧w動(dòng)作時(shí),通常不用could,而用be able to。如果表示某一動(dòng)作沒有取得成功,則可用 couldn’t: It’s a pity he couldn’t visit Mary. 很遺憾他沒能去看望瑪麗?! h, didn’t you know? He was able to visit her after all. 噢,你不知道嗎?他最終還是能去看她了?! ≡趩?wèn)及過(guò)去某一具體活動(dòng)時(shí)可用 could,但回答是肯定的時(shí)候則不能: Could he borrow a car? 他能借到車了嗎? Yes, he was able to borrow a car after all. 是的,他最終還是能借到車了?! o, he couldn’t. 不,他沒能借到。