Question

I .............. run a mile when I was young

(ability in the past). (Supply correct modal)​

Answer 1

Explanation:

I used to run a mile when I was young

Answer 2

I could run a mile when I was young.

• The sentence is required to be completed using a modal.
• These are the words that indicate the possibility or the likelihood of an event happening.
• The ability of the subject in the past can be clearly demonstrated by using 'could' and is the relevant modal here.
• So, the sentence means that the subject was capable of running a mile when he was young.