A compound comprising a first strand and a second strand, each of the strands being 19-29 monomers in length, the monomers comprising UNA monomers and nucleic acid monomers, wherein the compound has a duplex region of from 14 to 29 contiguous monomers in length, wherein the first strand is a passenger strand for RNA interference and the second strand is a guide strand for RNA interference, wherein the compound comprises a sequence of bases targeted to inhibit expression of an HBV genome, wherein the UNA monomers each independently have the following formula: wherein R 1 and R 2 are H or a phosphodiester linkage, Base is a nucleobase, and R 3 is selected from -OR 4, -SR 4, -NR 4 2, -NH(C=O)R 4, morpholino, morpholin-1-yl, piperazin-1-yl, or 4-alkanoyl-piperazin-1-yl, wherein R 4 is the same or different for each occurrence, and is selected from H, alkyl, a cholesterol, a lipid molecule, a polyamine, an amino acid, or a polypeptide, and wherein: the compound comprises one of the following pairs: SEQ ID NO: 987 and 988; SEQ ID NO: 993 and 994; SEQ ID NO: 999 and 1000; SEQ ID NO: 1005 and 1006; SEQ ID NO: 1009 and 1010; SEQ ID NO: 1011 and 1012; SEQ ID NO: 1013 and 1014; SEQ ID NO: 1015 and 1016; SEQ ID NO: 969 and 970; SEQ ID NO: 971 and 972; SEQ ID NO: 973 and 974; SEQ ID NO: 977 and 978; SEQ ID NO: 981 and 982; SEQ ID NO: 989 and 990; and SEQ ID NO: 997 and 998; or the compound comprises one of the following pairs: SEQ ID NO: 1145 and 1146; SEQ ID NO: 1175 and 1176; SEQ ID NO: 1149 and 1150; SEQ ID NO: 1163 and 1164; SEQ ID NO: 1165 and 1166; SEQ ID NO: 1167 and 1168; SEQ ID NO: 1169 and 1170; SEQ ID NO: 1153 and 1154; SEQ ID NO: 1155 and 1156; SEQ ID NO: 1157 and 1158; SEQ ID NO: 1161 and 1162; SEQ ID NO: 1159 and 1160; SEQ ID NO: 1147 and 1148; and SEQ ID NO: 1151 and 1152. the compound comprises one of the following pairs: SEQ ID NO: 987 and 988; SEQ ID NO: 993 and 994; SEQ ID NO: 999 and 1000; SEQ ID NO: 1005 and 1006; SEQ ID NO: 1009 and 1010; SEQ ID NO: 1011 and 1012; SEQ ID NO: 1013 and 1014; SEQ ID NO: 1015 and 1016; SEQ ID NO: 969 and 970; SEQ ID NO: 971 and 972; SEQ ID NO: 973 and 974; SEQ ID NO: 977 and 978; SEQ ID NO: 981 and 982; SEQ ID NO: 989 and 990; and SEQ ID NO: 997 and 998; or SEQ ID NO: 987 and 988; SEQ ID NO: 993 and 994; SEQ ID NO: 999 and 1000; SEQ ID NO: 1005 and 1006; SEQ ID NO: 1009 and 1010; SEQ ID NO: 1011 and 1012; SEQ ID NO: 1013 and 1014; SEQ ID NO: 1015 and 1016; SEQ ID NO: 969 and 970; SEQ ID NO: 971 and 972; SEQ ID NO: 973 and 974; SEQ ID NO: 977 and 978; SEQ ID NO: 981 and 982; SEQ ID NO: 989 and 990; and SEQ ID NO: 997 and 998; or the compound comprises one of the following pairs: SEQ ID NO: 1145 and 1146; SEQ ID NO: 1175 and 1176; SEQ ID NO: 1149 and 1150; SEQ ID NO: 1163 and 1164; SEQ ID NO: 1165 and 1166; SEQ ID NO: 1167 and 1168; SEQ ID NO: 1169 and 1170; SEQ ID NO: 1153 and 1154; SEQ ID NO: 1155 and 1156; SEQ ID NO: 1157 and 1158; SEQ ID NO: 1161 and 1162; SEQ ID NO: 1159 and 1160; SEQ ID NO: 1147 and 1148; and SEQ ID NO: 1151 and 1152. SEQ ID NO: 1145 and 1146; SEQ ID NO: 1175 and 1176; SEQ ID NO: 1149 and 1150; SEQ ID NO: 1163 and 1164; SEQ ID NO: 1165 and 1166; SEQ ID NO: 1167 and 1168; SEQ ID NO: 1169 and 1170; SEQ ID NO: 1153 and 1154; SEQ ID NO: 1155 and 1156; SEQ ID NO: 1157 and 1158; SEQ ID NO: 1161 and 1162; SEQ ID NO: 1159 and 1160; SEQ ID NO: 1147 and 1148; and SEQ ID NO: 1151 and 1152.