Question: As in subject I can't find "resolve" in context menu of Visual Studio 2010 Ultimate.
I have seen it in my teacher computer in the internet but I can't find it in the context menu, look at screen. How to get it?

![enter image description here](https://i.stack.imgur.com/yI5MM.jpg)

Answer: 
Type in `File.Open("Test.txt");` Then click on `File` en see if you can find resolve then. Should be able to resolve it to `System.IO.File`.

And for the record, you opened the context menu on a function. A function can't be resolved only types. So you could instead just type: `Debug` then open the context menu and resolve it to `System.Diagnostics`. Then you could call the `WriteLine` function. 

So besides your question, you need `System.Diagnostics.Debug.WriteLine(object)` instead of `System.Diagnostics.Debugger.WriteLine` which doesn't exist.
A long shoot - Maybe you write the wrong name of the function. So VS just can't resolve it for you?

If not, the resolve only adding `Using` statement to the beginning of the file in order to resolve the issue. For that you project must have the correct reference to the library which have the function. you can use the "Solution Explorer" (the right menu in your attached picture) and under the project you have the tab of "References" make sure it's there and if not right-click and "Add Reference..."