the planes had been planting seed for nearly month when it began to rain求翻译和解释

the planes had been planting seed for nearly month when it began to rain求翻译和解释
the planes had been planting seed for nearly month when it began to rain
求翻译和解释

the planes had been planting seed for nearly month when it began to rain求翻译和解释
when引导时间状语从句
　　when是引导时间状语从句最常用的一个词,它涵盖的时间范围比较广泛,在作“当……的时候”解时,有下面几种常见用法：
　　1.表示在某个具体的时间里发生的动作.此时,when不能用as或while替换.
　　When she comes,I shall tell her to wait for you.她来的时候我会告诉她等你的.(指具体的时间点)
　　When his father died of illness in 1980,he was only two years old.1980年他父亲病逝时他只有两岁.(指1980年这个具体的时间点)
　　2.表示一个动作与另一个动作在同一时间发生,或一个动作在另一个动作所延续的时间范围之内发生.此时,when可以用as或while替换.
　　I hurt my shoulder when (while,as) I was playing basketball.我打篮球时弄伤了肩膀.
　　He entered the room when (while,as) the meeting was going on.正当开会的时候他走进了房间.
　　When (While,As) Tom was reading,Jim was writing.汤姆看书的时候,吉姆在写东西.
　　两个同时发生的动作,如果不是一次性而是重复性的,即过去或现在的习惯动作,可用连词when或whenever,意思是“每当……的时候”.例如：
　　When (Whenever) he goes to town,he always visits his aunt.每当他去镇上,他都去拜访他姑姑.
　　She always felt ill when (whenever) she ate oyster.她每次吃牡蛎都会生病.
　　在上述两例中,不管是用when还是用whenever,主句动词和从句动词或者都用一般现在时,或者都用一般过去时,分别表示现在或过去的习惯动作.
　　3.表示从句的动作发生后,主句的动作立即发生.此时,when表示动作的先后顺序,相当于after,不能用as或while替换.
　　When he had done his homework,he watched television.=After he had done his homework,he watched television.他做完作业后看电视.
　　When he had painted the windows,he painted the doors.=After he had painted the windows,he painted the doors.他把窗户油漆完后,又把门油漆了.
　　在这里,when从句的谓语动词都用了完成体,when从句既可以置于句首,也可以置于句尾.但是,如果when从句的谓语动词用一般现在时或一般过去时,when从句只能位于句首,表示从句动作先于主句动作.
　　When he had done his homework,he watched television.=He watched television when he had done his homework.
　　When he had painted the windows,he painted the doors.=He painted the doors when he had painted the windows.
　　但是,“When he painted the windows,he painted the doors.”这个句子则不能写成“He painted the doors when he painted the windows.”
打字不易,