题干
.
.The speech which he made ______ the project has bothered me greatly.
.The speech which he made ______ the project has bothered me greatly.
A：being concerned
B：concerned
C：concer
D：concerning
答案(点此获取答案解析）
D
”）各一个及连接导线，闭合开关，电动机顺时针转动，LED亮，将电动机一端连线断开，闭合开关，LED亮． 
