What is “Could” Used For?

In English, could is the past tense form of can when we talk about ability. Just as can shows present ability (e.g., “I can swim”), could is used to talk about an ability someone had in the past.

How to Use “Could” for Past Ability

Using could in the past tense is pretty straightforward:

1. For General Abilities in the Past
   When we talk about things someone was generally able to do anytime in the past, could is the right word to use.

   Examples:

   • “When I was younger, I could run fast.” 🏃‍♂️
   • “She could speak Spanish fluently when she lived in Mexico.”

   Could here indicates that these were abilities that the person had for a period of time in the past.

2. For Specific Situations in the Past (Negative Form)
   In specific past situations where someone was unable to do something, couldn’t or could not is used.

   Examples:

   • “I couldn’t find my keys this morning.”
   • “They couldn’t solve the puzzle even after trying for hours.”
3. When Not to Use Could
   If we’re talking about one specific moment in the past and it’s a positive ability (meaning the person was able to do it at that moment), could usually isn’t used. Instead, we might say was able to or managed to.

   Examples:

   • Specific: “He was able to finish the project by the deadline.”
   • General: “He could finish his projects on time.”

Practice Examples

Let’s check out some sentences to see if you understand how to use could for past ability:

1. “When I was in school, I _______ (play) the piano very well.”
   • Answer: could play
2. “Last night, we _______ (not/find) a taxi, so we walked home.”
   • Answer: couldn’t find
3. “She _______ (run) faster than anyone in her class.”
   • Answer: could run
4. “Yesterday, I _______ (not/finish) my homework on time.”
   • Answer: couldn’t finish

Quick Tips for Remembering

• Use could for general past abilities (skills you had at any time in the past).
• Use couldn’t for inability in specific past situations or general past limitations.
• For one-time achievements in the past, try using was able to instead of could.