He is often heared playing the violin at home.完整的原句的不能删减是双宾语从句啊有俩答案语法我不太懂啊，平时讲的时候只凭语感。其他人的答案应该好一些吧。还有，第一句里heard写错了。The violin played by him is often heard by us at home.这样应该也可以吧。