As a child, couldn't/didn't manage to swim.
couldn't
In 2019, Eliud Kipchoge managed to/could run a marathon in under two hours.
both
Can you/Will you manege to help me with my training this evening?
Can you
After these French lessons, I 'll be able to/can make friends when I go to France next year.
'll be able to
Our school wasn't able to/couldn't compete in the national schools swimming championship.
both
We didn't manage/werent able to watch the final on TV last night.
both