Consider these sentences:
The ice was thick enough to walk on.
They were in a hurry.
There is enough salt in it.
It is freezing.
I am right.
Are the italicized verbs auxiliary verbs?
Update: Let me explain why I asked this question.
The above sentences are from exercise 6 "Auxiliary verbs" from the book "A Practical English Grammar Exercises 1".
From the 36 sentences in exercise 6, all except the above mentioned five sentences are indeed sentences that contain auxiliary verbs (may, must, can, will, had, etc.).
So, what happened here? Why are those five sentences in this exercise? Is it an oversight?

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