The simple answer is ‘Please’. 

Basically, the –lah at the end of a word is added to make the sentence sounds more polite. Similar to when you want to ask your guest to sit down, instead of saying “Sit!” you will say “Please sit down.” to make it sound more inviting and less authoritative. 

In Indonesian, usually if –lah combines with a verb, it will have the same meaning as adding the word ‘please’. Example:

Duduk! 🡪 Duduklah

Makan! 🡪 Makanlah

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