nailed on
adjective UK informal (also nailed-on) uk/ˌneɪld ˈɒn/ us/ˌneɪld ˈɑːn/
非常确信，非常肯定
very certain or definite
His breaking the goalscoring record for Ireland now seems nailed on. 他将会打破爱尔兰进球纪录，这是非常肯定的。
South Africa were nailed-on favourites to host the 2010 World Cup. 南非非常肯定是举办2010年世界杯的大热门。