Definition: Rewrite each original sentence in order to make it easier to understand by non-native speakers of English. You can do so by replacing complex words with simpler synonyms (i.e. paraphrasing), deleting unimportant information (i.e. compression), and/or splitting a long complex sentence into several simpler ones. The final simplified sentences need to be grammatical, fluent, and retain the main ideas of their original counterparts without altering their meanings.
Input: With little warning, a second earthquake of magnitude 5.1 May 18 triggered a massive collapse of the north face of the mountain.

a large earthquake suddenly hit on the 18th of May and damaged the north of the mountain.