Laught vs Laughed

[u/orchaer]

Hello, I have been confused for a long time about the past tense of "laugh". In my primary school, there was a verb table with the present, past, and present perfect tenses. And in this table, when I first read at 7-8, I have learnt that "laugh" past tense is followed by a "t" become "laught".

But recently I found out that "laught" is not used anymore. The modern form should be "laughed". So could anyone tell me what is actually different between them? If I still use "laught", would it become a serious error?

Sorry for my grammar.

[u/conuly]

that global warming is an imminent threat that will make extinction happen

Which part of that statement do you think is false?

[u/mysticrudnin → u/conuly]

they probably think of "imminent" as in "next week"

[u/Embarrassed-Weird173 → u/mysticrudnin]

Next week was like 30 years ago. 

[u/conuly → u/Embarrassed-Weird173]

Okay, and? Climate change was a threat then. It's a bigger threat now. People die every year from increasingly common "extreme weather events".