To write the report,research must be done(改错 此句修饰语悬垂）

前面的都OK，还有一种：
Research must be done for (表目的）writing the report.

to write the report，we have to finish the research

悬垂修饰语是指句首的短语与后面句子的逻辑关系混乱不清
To write the report,we must do the reserach.