How does the author use foreshadowing in Good-bye, Mr. Chips?

In Chapter Five, the evening before the wedding, Katherine made a point to say goodbye to Mr. Chips for the last time before they became a couple. She thought it appropriate to say, "Good-bye, Mr. Chips."

The New Woman that Chips was so fearful of proved to be his greatest supporter. He remembers how she laughed at him for his self-deprecating remarks. When she
tenderly says "Good-bye, Mr. Chips" the night before their wedding, she is marking the end of the man who didn't believe in himself. This is a masterfully emotional episode—understated, yet touching and poignant. Even though, for reasons unknown yet, they are no longer together, she is ever-present in his memory and he still loves her. There is the foreshadowing of a tragedy and great sadness involving Katherine.