Difference between 忽然 and 忽然間

[Koxinga]

In the graded reader I'm reading, there's "忽然¹間" at the start of a sentence. I asked a Chinese speaker about it, and the answer I got was that 忽然 and 忽然間 mean the same (suddenly). However, the footnote only explains 忽然.

Actually I only know 間 as part of 房間 and 時間. Can someone offer an explanation?

[skylee]

I think 忽然 can be used as an adjective or an adverb, whereas 忽然間 is used as an adverb.

PS - 間 refers to a duration of time. For example, 談笑間強虜灰飛煙滅，as in the famous poem.

[Koxinga]

Thanks, skylee! Could you also provide an example when 忽然 can be used and 忽然間 cannot?

[benjamincai]

skylee have a good point on this. Also, you can use 突然 instead of 忽然, they are the same.

Let me get back to the point first. 間 is a word about time.

For example you can say

忽然間，小明跌倒在地上。

小明忽然間跌倒在地上。

Actually almost all the case you can interchange them. No different.

By the way, you can also use 忽然之間 this is more popular.

However, in speaking, people tend to use 突然 more than 忽然.

Hope this can answer your question.

[歐博思]

忽然（间）发生了事故，这一切来得也太突然（/ 忽然？）啦。

The presence of 间 forces it into an adverbial role. In the second half of the above sentence using 间 on either 突然 or 忽然 would be incorrect.

Is there really no different feeling between 忽然 and 突然？

Not a native speaker.

[szcube]

As a native speaker I would like to say there is only a subtle difference betwwen 忽然and 突然.

You can almost ignore it.But if you really want to know the difference.

突然 is a adj,adv

忽然is only a adv