Tena koutou e te iwi whanui!

This is the last entry (for now haha) on the Strong Imperative which focuses on the reflexive, basically if the command issued is regarding oneself. Ray Harlow puts it as below in his book A Maori Reference Grammar:

"... An exception to the rule that transitive verbs with object use the passive for commands is found in sentences with a reflexive object, where the patient of the ction is the same person/people as the subject. In this case, the passive suffix is not used and the object is marked with 'i':"

Whakapaipai i a koe! - Make yourself look pretty!

Horoi i a koutou! - Wash yourselves!

I also give further examples which follow the above structure:

Horoi i ou makawe - Wash your hair!

Horoi i ou ringaringa - Wash your hands!