The instrument ____ was not in the laboratory.A.which the professor referred usB.to which the professor referred usC.to which the professor referred to usD.which the professor referred to us

英语翻译：这个乐器是他自己发明的.The instrument is ____ ____ invention. ____ of plastics,the instrument is light.(make）时态填空,请写明原因 instrument可数吗为什么可以说play an instrument?有play the instrument的说法吗 instrument instrument piano is a kind of musical instrument 还是the piamo is a kind of instrument The instrument ____ was not in the laboratory.A.which the professor referred usB.to which the professor referred usC.to which the professor referred to usD.which the professor referred to us 翻译 How long can I keep the instrument? The instrument was bought by my grandfather many years 一道非谓语的选择题____ at first to accomany dancing,the violin was considered an instrument of low social status.A.Being used B.Having been used C.Used 选哪一个?别的为什么不对? A violine is a kind of ____(music) instrument.谁若知道就告诉我, Instrument Consumable instrument是什么意思? instrument是什么意思 instrument是什么意思 instrument是什么意思 instrument是什么意思 It was my grandfather who bought the instrument many years ago可以写成my grandfather has bought the instrument many years 还有为什么一定要it做形式主语?直接my grandfather who bought the instrument many years ago不行吗? my favorite instrument is (the) piano.之中的这个括号（ the）用加吗?为什么