newbie question about use -- thanks

[David Rod]

Hi 
I have been using gnus over 3 days.
In groups buffer I type AA to get a list of groups
This takes a long time
How do I get from this list back to the normal groups view without using
t to toggle the mode as topics?
How can I look at a list of newsgroups which is retained locally without
having to do AA each time which takes ages.
If I do A z I get the zombie groups, so it stands to reason that the
local machine must know where non-zombie groups are also.

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