(a):
a1 He said there was no cure for what I had.
a2 He said that what I had could not be cured.
(b)
b1 This injection will not hurt, I assure you.
b2 You will not feel any pain during this injection, I assure you.
(c)
c1 It is impossible to reverse the ageing process.
c2 The ageing process cannot be reversed.
(d)
d1 The dispute lasted long enough.
d2 It's high time we found a solution to this dispute.
