我的新西兰2年多次签，每次可以待多长时间？

This visa expires 1 month(s) after each arrival.Stay subject to grant of entry permission.You must leave before visa expiry or face deportation.The holder shall not undertake employment in NZ .The holder shall not study for more than 3 months in every 12 month period in NZ.请英语高手指教。