Would this work?
A={(a,b,c,d,0,e,f,g,h,0)}
B={(a,0,b,c,d,e,f,g,h,i)}
Then A and B span R^10 since a linear combiantion Q(a,b,c,d,0,e,f,g,h,0) + P(a,0,b,c,d,e,f,g,h,i) = (Qa+Qb,Qb,Qc+Pb,...) = (x1,x2,x3,x4,x5,x6,x7,x8,x9,x10).
And also A∩B i think is equal to {(a,0,b,c,0,d,e,f,g,0).
Is that...