Question about variable name autocompletion in $Mathematica$ 9 on OS X

For the command autocompletion, I can simply use Ctrk+K and then use Return or Tab to choose the completion. But when I want to autocomplete the local variables I have input, Ctrk+K works, but both Return and Tab fail to input the variable's name. I have tried to change this behavior with the Interface panel of the Preferences dialog , but there are no options I can change. Do you know some easy to make Return and Tab work for local variable autocompletion?

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I have Mathematica version 9.0.1 on OS X 10.9.1, and I find that autocompletion of local variables works when I have the notebook's default context set to be Global, but not when it is set to be Unique to This Notebook. –  Stephen Luttrell Dec 26 '13 at 11:06
You are right! I just tried and it indeed work when the default context is Global. What I met is when editing .m file, and the context is not Global but my package. So the problem is the context, what should we do? –  wxg Dec 26 '13 at 11:33
Are you sure you mean control+k and not command+k? Also, what do you mean by local variable? I get no autocompletion options for Block[ {hello} , hell (*cursor here*) ] when writing it the first time, but the fact that the variable is local does not matter I think. After evaluating the cell, hello is now available for autocompletion anywhere, also outside the Block. It seems symbols from the Global context are autocompleted, no matter the option notebook's default context. If this option is set to unique for this notebook, new symbols are simple not added to Global. –  Jacob Akkerboom Dec 26 '13 at 12:04
Thank you for comment. In my mac it is cmd+k. I have tried Block[ {hello} , hell (*cursor here*) ], and the autocompletion works. By local variable I mean variables appear in Block and Module. I only have the problem when writing *.m file not notebook file. –  wxg Dec 27 '13 at 15:02
Very similar to this question, –  m_goldberg Dec 27 '13 at 23:31