Disclosed herein are conjugated modified oligonucleotides of formula (I) that are complementary to a target RNA, wherein each N of Nm is, independently, a modified or unmodified nucleoside and m is 1 or 2； X1 and X2 are each, independently, a phosphodiester linkage or a phosphorothioate linkage； and MO is a modified oligonucleotide consisting of 8 to 25 linked nucleosides and comprising at least one nucleoside with a cEt modified sugar moiety, wherein the nucleobase sequence of the modified oligonucleotide is complementary to a microRNA. The conjugate facilitates cellular uptake of the modified oligonucleotide, resulting improved potency.
