People visit the winter light show at the Palm Garden in Frankfurt, Germany, on Dec. 15, 2018. The light show is held here from Dec. 15 to Jan. 20, 2019. (Xinhua/Lu Yang)

A child looks at a light installation during the winter light show at the Palm Garden in Frankfurt, Germany, on Dec. 15, 2018. The light show is held here from Dec. 15 to Jan. 20, 2019. (Xinhua/Lu Yang)

A woman visits the winter light show at the Palm Garden in Frankfurt, Germany, on Dec. 15, 2018. The light show is held here from Dec. 15 to Jan. 20, 2019. (Xinhua/Lu Yang)

Photo taken on Dec. 15, 2018 shows the winter light show at the Palm Garden in Frankfurt, Germany. The light show is held here from Dec. 15 to Jan. 20, 2019. (Xinhua/Lu Yang)

People visit the winter light show at the Palm Garden in Frankfurt, Germany, on Dec. 15, 2018. The light show is held here from Dec. 15 to Jan. 20, 2019. (Xinhua/Lu Yang)