So, having had a look into the HSK5 vocab which involves the character 大, I have come across a few instances where I am not sure what is used in which circumstance.
重大 vs 严重 - these both mean important/critical in an objective sense (rather than 重要, which is subjective). But, when you choose 重大 over 严重? You seem to be able to say 重大事件 and 严重事件 - does anyone know what the difference between these two critical situations is? I think you would call 911 in both circumstances, right?
广大 vs 大型 vs 巨大 - these all mean 'massive/humongous'. There likewise doesn't seem to be much difference between them. Maybe 广大 is more related to surface area (horizontal) while 大型 and 巨大 are more vertical in scope? Not sure...
Any input would be much appreciated!