The modal verb 来
Modal verbs (情态动词) can be used to express possibility, desire, ability, and necessity. Modal verbs cannot appear without a predicate and can only appear in predicate phrases.
The modal verb 来 
has an imperative coloring and expresses an offer to do something.
has an imperative coloring and expresses an offer to do something. Pay attention
The particle 吧 often comes at the end of sentences with 来.
often comes at the end of sentences with 来.Examples
你来念一遍
You read it out loud
nǐ lái niàn yíbiàn
我来帮你提箱子吧
Let me help you with your suitcase
wǒ lái bāng nǐ tí xiāngzi ba
工作有困难, 大家来想办法
There are difficulties at work, so let's think about it
gōngzuò yǒu kùnnan, dàjiā lái xiǎng bànfǎ