The farmer had to wear heavy boots in the winter because the fields were too wet and________.
D
暂无解析
________somanypeopleintheUnitedStatesbeenoutofworkastoday.
Itisusefultoscience_______theearthasanobjectinspace.
Constructionoftherailwayshelpedtodevelopthenational_______ofTanzaniaandZambia.