用must,can,can't填空，完成对话。

KATE: ____1____you recognize that woman.Liz?

LIZ:I think I____2____,Kate. It____3____be Karen Marsh,the actress.

KATE:I thought so. Who's that beside her?

LIZ:That____4____be Conrad Reeves.

KATE:Conrad Reeves,the actor? It____5____be.Let me have another look.I think you're right!  Isn't he

          her third husband?

LIZ: No.He____6____be her fourth or fifth.

KATE:Doesn't Karen Marsh look old?

LIZ:She does,doesn't she?I read she's twenty-nine,but she____7___be at least forty.

KATE:I'm sure she is.

LIZ:She was afamous actress when l was still at school.