18000
 Largely bombed out by the Germans in World War II , Rotterdam , the second largest city in the Netherlands after Amsterdam , has completed over the last 20 years several successful urban renewal projects that have left it with a thriving local economy the largest commercial port in the world . 
 country capital: Netherlands, Amsterdam
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: nationality, country capital, place of death, children, location contains, place of birth, place lived, administrative division of country, country of administrative divisions, company, neighborhood of, company founders 
Text: {0} 
Answer:
 country capital: Netherlands, Amsterdam