Then, like so many people, who, perhaps, ought to be issued only a very probational pass to meet trains, he tried to empty his face of all expression that might quite simply, perhaps even beautifully, reveal how he felt about the arriving person.
There are no more uses of "probation" in the book.
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The judge sentenced her to three years of probation instead of sending her to prison.
I start the new job next week, but my medical insurance will not begin until after a sixty day probationary period.