A) should have died B) must be dying
C) must have died D) ought to die
68. The energy ______ by the chain reaction is transformed into heat.
A) transferred B) released
C) delivered D) conveyed
69. ______ their work will give us a much better feel for the wide differences between the two schools of thought.
A) To have reviewed B) Having reviewed
C) Reviewing D) Being reviewed
70. During the process, great care has to be taken to protect the ______ silk from damage.
A) sensitive B) tender
C) delicate D) sensible