构。

　　Can you tell me who(m) do we have to see?(╳)

　　Can you tell me who(m) we have to see?( √)

　　The teacher asked the students what they were doing.(思考: what在从句中的成分)

　　陈述句变为宾语从句时,要注意人称和时态的变化,语序不变。 eg. She said, “I will leave a message on the desk.” à She said

　　she would leave a message on the desk.

　　一般疑问句和特殊疑问句变为宾语从句时,也要注意人称和时态的变化,后面接陈述语序。Eg. “Where are the tickets?” I asked him.

　　à I asked him where the tickets are.

　　三、宾语从句的时态呼应：

　　宾语从句中谓语动词的时态，常常受到主句谓语时态的制约，此为时态呼应。如果主句谓语是一般现在时或将来时，从句谓语的时态不受

　　限制;如果主句谓语的时态是一般过去时，从句一般要随着改为相应的过去时态(一般过去时、过去进行时、过去将来时、过去完成时)。