Weak two bids.  

Good bids in first or second seat, no promises in third seat.  
A fourth seat weak two bid should be almost an opening hand - 
it is not necessarily preemptive because you could go zero 
for passing so if you open you must go plus to make it worth 
your while.  

A two no trump response is asking for a feature.  A feature 
is defined as an ace or king outside the trump suit.  If you 
don't have one, rebid your suit.  If your suit is AKQXXX, 
answer by bidding 3NT
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