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Part 2 · Episode 18 B1-B2

I Could Have Been Great

📐 could have (missed opportunity/unrealized potential)

Marlon Brando · 1950s: Marlon Brando's famous lament 📖 6 min read

Episode 18: I Could Have Been Great

could have: missed opportunity — Marlon Brando, 1950s (B1-B2)

Grammar Box

Meaning: “Could have + past participle” expresses unrealized potential or missed opportunities—when something was possible in the past but didn’t happen, often with a sense of what might have been.

Form: could have + past participle; couldn’t have + past participle

Example 1: “I could have been a professional athlete.” (past potential that wasn’t realized)

Example 2: “We could have won if we’d tried harder.” (missed opportunity)

Common mistake: Wrong: “I could have be successful.” Better: “I could have been successful.” (could have + past participle)

The Challenge

Luna found an old acceptance letter from a prestigious university she had turned down years ago. “I could go there,” she said wistfully. Professor Wisdom appeared, correcting gently, “Could go now, or could have gone then?” Luna felt the weight of that small grammar change—the difference between present possibility and past opportunity forever closed. The watch glowed with a bittersweet light, taking them to a moment when one of cinema’s greatest actors spoke about the gulf between potential and reality.

The Journey

Marlon Brando stood on a film set in the 1950s, between takes of “On the Waterfront,” preparing to deliver one of cinema’s most iconic speeches. As Terry Malloy, a former boxer turned dock worker, Brando would speak lines that resonated far beyond the script: “I coulda been a contender. I coulda been somebody, instead of a bum, which is what I am.”

The scene captured a universal human experience—the painful recognition of unrealized potential. Terry’s brother had forced him to throw a fight years earlier, derailing his boxing career and leaving him to wonder what might have been. “You don’t understand,” Terry says in the film. “I coulda had class. I coulda been somebody.”

Brando himself understood this feeling deeply. Though he became one of the greatest actors of his generation, he often spoke about paths not taken, potential unfulfilled. “I could have been a serious classical actor,” he told interviewers later in life. “I could have dedicated myself to theater instead of Hollywood. I could have chosen roles more carefully instead of taking parts just for money.”

The power of “could have” lies in its acknowledgment of real possibility. Unlike “would have,” which might be pure fantasy, “could have” suggests something genuinely attainable that circumstances, choices, or chance prevented from happening. Terry Malloy really could have been a champion boxer—he had the talent and opportunity until his brother’s betrayal closed that door forever.

The scene required multiple takes as Brando and director Elia Kazan perfected the emotional tone. The smell of the waterfront set—salt water, old wood, urban grit—provided atmosphere as Brando channeled the regret of missed opportunities. “I could have been better,” he muttered between takes, perhaps speaking as much about his own life as his character’s.

Years later, Brando’s “could have been” became more pronounced. Despite his legendary status, he often expressed disappointment with his career choices. “I could have made more meaningful films,” he said. “I could have used my platform for greater social impact. I could have been more disciplined, more selective, more committed to the craft.” Each statement acknowledged genuine possibility that remained unrealized.

The Deep Dive

“Could have + past participle” expresses unrealized potential—what was genuinely possible in the past but didn’t happen. This differs from “should have” (which carries judgment about what was right) and “would have” (which describes what would happen in hypothetical conditions). “I could have been a doctor” simply states the possibility existed, without necessarily implying you should have chosen that path or would have under different circumstances.

The emotional tone of “could have” is complex. It can express simple acknowledgment of past possibility (“I could have taken the train instead”), nostalgia for roads not taken (“I could have lived in Paris”), or deep regret about missed opportunities (“I could have been with her”). Context and tone determine whether it’s matter-of-fact or emotionally charged. Often, the construction appears with “but”: “I could have succeeded, but I gave up too easily.”

Don’t confuse “could have” for unrealized potential with “could have” for past possibility or ability. “He could have been lying” (possibility/deduction) differs from “He could have been a great pianist” (unrealized potential). Also distinguish it from “couldn’t have,” which expresses impossibility rather than missed opportunity. When expressing regret about potential, “could have” is gentler than “should have”—it observes what was possible without harsh self-judgment about what was right.

More Examples

History: “The Roman Empire could have survived longer if internal conflicts hadn’t weakened it.” (historical missed possibility)

Science: “That cure could have been discovered decades earlier with more funding.” (unrealized potential due to circumstances)

Everyday: “I could have been fluent in Spanish by now if I’d kept studying.” (acknowledging missed opportunity)

Formal: “The partnership could have been highly profitable under different market conditions.” (professional analysis of unrealized potential)

Informal: “We could have been friends if we’d met under different circumstances.” (wistful acknowledgment)

Contrast: “I should have studied harder” (regret with judgment) vs “I could have studied harder” (acknowledging possibility without moral weight) vs “I must have studied harder than I thought” (deduction)

Practice & Reflection

Exercises:

  1. Fill in the blank: With more practice, she __ (could have/should have) become a professional musician.

  2. Correct the mistake: “He could have became a famous writer if he’d finished his novel.”

  3. Choose and explain: Which expresses unrealized potential?
    a) “I should have taken that job.”
    b) “I could have taken that job.”

  4. Rewrite: Express missed opportunity: “I had the ability to play professional basketball, but I chose a different path.”

  5. Compare: Explain the difference: “I could have won” vs “I should have won” vs “I must have won.”

  6. Your reflection: Think of a path you didn’t take. Write about it using “could have” to express unrealized potential.

Answer Key:
1. could have become (states potential existed without judgment)
2. He could have become a famous writer (past participle “become,” not “became”)
3. (b) — “could have” simply notes possibility; “should have” adds judgment about rightness
4. I could have played professional basketball, but I chose a different path (unrealized potential)
5. First = missed possibility; second = regret (should have won but didn’t); third = deduction (believe I won)
6. Check: Does “could have + past participle” express genuine past potential that wasn’t realized?

The Lesson

Luna put away the old acceptance letter with bittersweet understanding. “I could have gone to that university,” she told Professor Wisdom. “It was a real possibility. But I chose differently, and that’s okay. The potential was there, even if I didn’t pursue it.” The Professor smiled gently. “Exactly. Brando’s character and Brando himself both understood ‘could have’—it acknowledges real possibilities without demanding you regret them. Sometimes recognizing what we could have been helps us appreciate who we became. The grammar allows you to honor both the path taken and the paths not taken.”