In a classic mendelian monohybrid cross between a homozygous dominant parent and a homozygous recessive parent, which generation is always completely heterozygous

T- dominant allele
t- recessive allele

parental cross: homozygous dominant parent (TT) and a homozygous recessive parent (tt)
The parental cross is true-breeding, so: TTx tt

The F1 generation will be all heterozygote: Tt      
The F1 generation will be 100% heterozygote

Reproduction i think