Makibi SHIMOTSU was appointed as a member of the Japanese envoy to the Tang Dynasty of China in 716 when he was 22 years old, and visited Tang in the following year, 717.
716年（霊亀2年）、下道真備は22歳のときに遣唐留学生となり、翌年の717年（養老元年）に入唐した。