In the case of the amino acid leucine alone, there are six different codons (TTA, TTG, CTT, CTC, CTA, and CTG) that can recognize and translate tRNA. Since there is only one codon to be translated, only one tRNA is required.
The anti-codon in the tRNA identifies complementary positions on the codon, and due to the characteristic of the third-base motif, there is no 1: 1 ratio between the number of codons present and the required anti-codon.
