to the east,on the east,in the east的区别

in the east 在.之内的东部.
to the east 在.之外（不紧密相邻）的东部.
on the east和.相邻的东部.
1. in表示A地在B地范围之内.如：
Taiwan is in the southeast of China.
2. to表示A地在B地范围之外,即二者之间有距离间隔.如：
Japan lies to the east of China.
3. on表示A地与B地接壤、毗邻.如：
North Korea is on the east of China.