What are advantages and disadvantages of using foreign workers in a country?

There will definitely be a mjor disadvantage!! VEry soon, it wont be our country anymore, but rather, their country!! It's very dangerous!! IMagine, when they decide to stage an uprising due to unfair treatments?? With their population more than citizens, how are our citizens gonna fight them all?? As such, it's the government responsibilities to tackle such a problem, for they are the ones whom approved of those foreign workers..

main advantage is the cheap labor. there are so many disadvantages, like the money earned will go in another country bad for that countries economy. overpopulation, socially disadvantages

advantages : they sometimes bring the good habit and good work ethos to my country disadvantegs : sometimes they bring too a bad culture in my country