The snowstorm ________ our difficulties. A．added to B．added

The snowstorm added to our difficulties.为什么要加to,add是及物动词呀 Added to our His coming _our happiness.A.added B.added to C.added up D.ad 英语翻译Success added to our pleasure Successfully added to our what he did has added to our difficulties为什么用现在完成时 nothing added to our understanding of the math problem The money he spent ____ more than $5,000.A.added B.added up the great wall has been_several times.A.added B.adding to C. culture and art are added to our teaching to develop the chi （1）A adds to B 和 A is added to B 有什么区别? what he did has added to out difficulties.这个句子里面OUT是什么意思?还有分 it is nothing but time A.to add B.to be added c.adding D.add