[deadthinker]

i was wondering if anyone could help me.
in april it is likely i will be moving to work in tokyo, japan. i would confirm the job before moving however so that isnt a problem and i dont seem to have any problems with a visa etc. but i am a british citizen i dont want to sound stuck up at all but a british passport is a good thing to have and is important to me as i will be returning here in around a year +. i was wondering if anybody knew how often i have to return home in order to keep my british citizenship?
also with the job i will be doing i only need english language but i understand i will need japanese aswell. i already studied for some time and graduated my course with japanese 1 although this is only basic do you believe this will be ok for the time being since most conversations i will have will be in english and the people i am staying with speak only english. i have thought about times when i would need japanese and for most situations i can think of i would be able to hold a conversation well, but i wondered your advise on this.
any advice would be greatly appreciated ^^