There are many Qur'anic verses in which Allah talks about Himself in the plural expression. For example , Allah said:
"Indeed, it is We who sent down the Qur'an and indeed, We will be its guardian".[The Qur?an 15:9]
Allah uses plural expression such as "We" to stress His Greatness and His Majesty. This does not mean that Allah is more than one because the Oneness of Allah is the most essential creed which a believer has to fulfill. Allah said:
Say, "He is Allah , [who is] One, Allah , the Eternal Refuge. He neither begets nor is born, Nor is there to Him any equivalent".[The Qur?an 112:1-4]
Also Allah said:
"And your god is one God. There is no deity [worthy of worship] except Him, the Entirely Merciful, the Especially Merciful". [The Qur?an 2:163]
That we is used for Allah, in translations it is mentioned like that but it is singular and used for Allah. So it is equally important to know the language in its original form. Translations are not what is exactly said, but is near to what it is said.