i will go to my cousin's house at 10.
i will play and it will be very fun.
my cousin are = is kind and humorous.
i don t have plant go there. = I don't really have a plan in going there.
i don t know play what and go where. = I don't know what will I do or where will I go. 
but i know this.......=  But one thing I know
tomorow i am going to go = my cousin's houses and comr = come back here ai on monday. 

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Hi Nain! Even though you don't have a plan just enjoy your visit in your cousin's house. ^^