Select all that apply: which sentences use a correctly formed obligation phrase for their stated time?
Last night, the bakery had to close when its oven failed.✓الإجابة الصحيحة
Every diver must to check the pressure gauge before descent.
The night guard must check each fire door before midnight.✓الإجابة الصحيحة
Next spring, the club will have to renew its river permit.✓الإجابة الصحيحة
الشرح
Had to close matches last night's past necessity, must check gives a present instruction, and will have to renew supplies a valid future form. The diver sentence is wrong because must cannot take to before the main verb.