一、at once
英 [æt wʌns] 美 [æt wʌns]
adv.立刻;立即;同时;一起
I recognized his voice at once.
我立刻听出了他的口音。
二、right away
英 [rait əˈwei] 美 [raɪt əˈwe]
就;立刻，马上;当时
They bought it right away.
他们立刻买了它。
三、at short notice
英 [æt ʃɔ:t ˈnəutis] 美 [æt ʃɔrt ˈnotɪs]
立即，仓促
He had to leave his previous quarters at short notice due to a fire.
由于失火，他不得不立即离开原来的住处。
四、in a minute
英 [in ə ˈminit] 美 [ɪn e ˈmɪnɪt]
马上，立刻
We'll broaden the discussion out in a minute.
我们马上要扩大讨论的范围
五、straight away
英 [streit əˈwei] 美 [stret əˈwe]
马上;立即
I should go and see a doctor straight away...
我得马上去看医生。
立刻，马上：immediately
英语例句：
Having played football for an hour, the boy was dusty and dirty and went to wash immediately.
那个男孩玩了一个小时足球，满身灰尘，便立刻去洗干净。
"They lit up immediately," she said.
“他们立即站了起来”，她说。
If you think your idea has potential, seize on it immediately.
如果你觉得某个想法很有潜力，立刻抓住它吧。
now表示这种意义，小学英语学到可用