按要求写句子。   

1．孩子们认真地完成了老师布置的作业。  

    改成“把"字句：                                                                                                            

    改成“被”字句：                                                                                                          

2．啜泣   持续不断的    哭泣   他   不时的   变成   那   低声

    连词成句：                                                                                                                             

高压无气喷涂机效率与（）关系不大