A:went; was occurring
B:went; occurred
C:was going; occurred
D:was going; has occurred
1999年,欧洲单一货币____的正式启用,推动了欧洲经济一体化。
调节手电筒使它发出的光会聚成狭窄的光柱(亦称“收光”)实际上是把灯泡的位置调节到凹形反光镜的( )
按拼音写汉字
hú lì pú táo chuí xià kǒu shuǐ fèi jìn chéng shú
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