Fill in the blank with suitable conjunction He will never pass, ______ hard he…

Answer: "However"

Example sentence: He will never pass, however hard he may try.

Explanation: "However" here introduces a concessive clause meaning "no matter how." It links the clause "however hard he may try" to the main clause to show contrast (i.e., despite his efforts).

Why the other choices are incorrect:

• "Whatever": Cannot combine with "hard" in this construction. It would need a different structure (for example, "whatever he tries") and does not express the intended concession.

• "Never": An adverb of frequency/time; it cannot introduce a concessive clause and does not mean "no matter how."

• "Whenever": Means "at any time when" (relates to time), so it does not express the concessive sense needed here.

Note: The previous solution called "however" a conjunctive adverb; in this sentence it functions as a conjunction introducing a concessive clause meaning "no matter how."