By the end of the year, all old generators ………….. with new ones.

Before the emergency cooling system activated, the temperature level ………….. the critical threshold.

WHICH IS CORRECT?

Had it not been for the immediate intervention of the automated system, the reactor ………….. out of control.

If the reactor temperature ………….. the critical level, the system ………….. power output automatically.

CHOOSE THE CORRECT FORM TO COMPLETE THE SENTENCE:

Only ………… reactors in the world have achieved sustained nuclear fusion. 

If the engineers ………….. the test earlier, they ………….. the critical cooling system failure.

The operator reported that the radiation level ………….. before the reactor startup.

WHICH SENTENCE IS CORRECT?

The chief engineer said that they ………….. a new safety module the following month.