Too many questions to answer all at once - I'll split them up.
The answer to 67 depends whether they're looking for the "traditional" explanation which would probably be :
One sentence uses future form (the first),
but two have future meaning (the first and second)...
or the more accurate explanation that
All three sentences use present form and meaning. which sees
will as being a normal first form verb with the present meaning of prediction (ie
I predict that...) or volition (
I am willing to.../ I promise/ I agree to). This also provides the answer to 68 -
One meaning of will is shown. ie volition. The sentences could be glossed as :
Are you willing to buy some coffee for me? I promise to pay you back....
You'll find a full discussion of the meanings of
will here