根据下列句子及所给汉语注释，在句子右边的横线上写出空缺处各单词的正确形式。（每空只写一词）
小题1:Only then did I realize the _____________(重要性) of learning English.
小题2:All countries, big or small, should be ___________.(平等)
小题3:The ___________(狭窄的) high way should be broadened.
小题4:__________(幸运地)， he passed the exam successfully.
小题5:He _____________(经历) a terrible traffic accident last month.
小题6:With the _____________(发展) of the economy, more and more people buy private cars.
小题7:We will remove the ______________(家具) from our house.
小题8:A policeman asked: “What _____________(引起) the fire in the hotel?”
小题9:The meeting will be held on next ____________ (星期三).
小题10:We must do something to reduce the air ________________.（污染）