How do I make this sentence imperative: "Nothing could stop him now."?

Related questions

• What are linking verbs, helping verbs, and action verbs? How are they different?
• What's the difference between a verb and an action verb?
• What is a passive verb? What are some examples?
• What is a linking verb?
• Is "is" a verb?
• What is a verb tense shift?
• What is a compound verb and some examples?
• What is the definition of an action verb?
• What's the difference between a verb, adverb, and adjective?
• What is a verb phrase?