reserve k,m,n for Nat, kk,mm,nn for Element of NAT, X,Y,x,y,z for set;
reserve S,S1,S2 for Language, s,s1,s2 for Element of S;

theorem Th2: S-termsOfMaxDepth.mm c= AllTermsOf S
proof
set T=S-termsOfMaxDepth; dom T=NAT by Def30;
hence thesis by ZFMISC_1:74, FUNCT_1:3;
end;
