Nasai なさい
Auxiliary verb used for making a strong, emphatic, or rude command form.
The standard negative command form is made by adding na to the dictionary form of verb. It is safer to use nasai only toward children. Adding yo after nasai will soft and the tone, however.
1.After conjunctive form of verb
答えを紙に書きなさい。
Kotae o kami ni kakinasai.
Write your answers on the paper.
早くしなさい。
Hayaku shinasai.
Hurry up and do it.
-> See also: kudasai, na
Japanese for Beginners