Before ___ the office, Ben checks if his computer is turned off.a) leavingb) have leftc) leftd) having left

To determine the correct answer, we need to analyze the sentence structure and the grammatical rules regarding verb forms.

1. Understanding Context: The sentence implies a condition where Ben performs an action (checking if his computer is off) before another action (leaving the office).

2. Verb Forms:

   • a) leaving: This is the gerund form of the verb and fits well to show an ongoing action.
   • b) have left: This is the perfect tense, which is not appropriate here because it indicates an action completed at some indefinite time.
   • c) left: This past tense form doesn't logically indicate the order of actions since it suggests the action has already been completed.
   • d) having left: This present participle form could imply that Ben checks something after he has left, but that does not fit the context of “before” his action of leaving.

3. Conclusion: The most grammatically correct form that fits the context of checking something before leaving is "leaving."

Final Answer

The correct answer is a) leaving.