顿时

顿时 immediately; at once

“顿时” means “immediately” and is used only when recounting a past event. It functions as an adverbial and does not take “地”.

1)我这么一说，他顿时觉得不好意思起来。

2)他的讲座一结束，大厅里顿时响起了热烈的掌声。

3)看到自己的球队踢进了一个球，球迷们顿时欢呼起来。

Compare: “顿时” and “立刻”

“顿时” is used to recount a past event, “立刻” does not have such limitation.“顿时” is only used in indicative sentences. It cannot be used in imperative sentences.“立刻” can be used in both,e.g.

1)好消息传来，人们顿时/ 立刻欢呼起来。

2)现在请同学们立刻到楼下集合。（ok）we can't say “请同学们顿时到楼下集合”（X）

3)他下了课，立刻就回家去了。（ok） we can't say “他下了课，顿时就回家去了。”（X）

4)我们明天一起床，就立刻出发 。（ok） we can't say “我们明天一起床，就顿时出发。”（X）