Complex sentence: The 2017 G20 Hamburg summit is the twelfth meeting of the Group of Twenty (G20) held on 7--8 July 2017 in the city of Hamburg (Germany).
Split into simpler sentences: The 2017 G20 Hamburg summit will be the twelfth meeting of the Group of Twenty (G20). It will be held on 7--8 July 2017 in the city of Hamburg (Germany).