A system including a composition and measurement circuitry, the composition including: a nanopore including a first side, a second side, and an aperture extending through the first and second sides; a plurality of nucleotides, wherein each of the nucleotides comprises an elongated tag that corresponds to the type of nucleotide, the elongated tag being sufficiently long and narrow to be disposed within at least a portion of the aperture of the nanopore; first and second polynucleotides, the first polynucleotide being complementary to the second polynucleotide; a polymerase disposed adjacent to the first side of the nanopore, the polymerase configured to add nucleotides of the plurality of nucleotides to the first polynucleotide based on a sequence of the second polynucleotide; a permanent tether including a head region, a tail region, and an elongated body disposed therebetween, the head region being anchored to the polymerase, wherein the elongated body occurs in the aperture of the nanopore; a first moiety disposed on the elongated body, wherein the first moiety is configured to bind to the elongated tag of a first nucleotide upon which the polymerase is acting; and a reporter region disposed on the elongated body; wherein the reporter region is configured to indicate whether the first nucleotide is complementary or is not complementary to a next nucleotide in the sequence of the second polynucleotide; the measurement circuitry being configured to measure a first signal state through the aperture generated responsive to the polymerase acting upon the first nucleotide and based upon the binding of the first moiety of the permanent tether with the elongated tag of the first nucleotide, the first nucleotide being identifiable based on the measured first signal state; and to measure a second signal state through the aperture it being determinable, based upon the second signal state, that the first nucleotide is complementary or is not complementary to the next nucleotide of the second polynucleotide. a nanopore including a first side, a second side, and an aperture extending through the first and second sides; a plurality of nucleotides, wherein each of the nucleotides comprises an elongated tag that corresponds to the type of nucleotide, the elongated tag being sufficiently long and narrow to be disposed within at least a portion of the aperture of the nanopore; first and second polynucleotides, the first polynucleotide being complementary to the second polynucleotide; a polymerase disposed adjacent to the first side of the nanopore, the polymerase configured to add nucleotides of the plurality of nucleotides to the first polynucleotide based on a sequence of the second polynucleotide; a permanent tether including a head region, a tail region, and an elongated body disposed therebetween, the head region being anchored to the polymerase, wherein the elongated body occurs in the aperture of the nanopore; a first moiety disposed on the elongated body, wherein the first moiety is configured to bind to the elongated tag of a first nucleotide upon which the polymerase is acting; and a reporter region disposed on the elongated body; wherein the reporter region is configured to indicate whether the first nucleotide is complementary or is not complementary to a next nucleotide in the sequence of the second polynucleotide; the measurement circuitry being configured to measure a first signal state through the aperture generated responsive to the polymerase acting upon the first nucleotide and based upon the binding of the first moiety of the permanent tether with the elongated tag of the first nucleotide, the first nucleotide being identifiable based on the measured first signal state; and to measure a second signal state through the aperture it being determinable, based upon the second signal state, that the first nucleotide is complementary or is not complementary to the next nucleotide of the second polynucleotide.