Grammar books say don’t use could for past performance. For example, if I ran after a bus and caught it, I can’t say “I ran after a bus and could catch it.”
Nevertheless, people say “I am glad that you could make it” to their guests.
2 Answers
If you are talking directly about something that happened in the past, you just use simple past:
I ran after a bus and caught it.
If you describe the same event in a that-clause, you have the option of focusing on the ability to do something, rather than on the doing itself, for example:
I was pleased that I could run fast enough to catch the bus. - ability
I was pleased that I caught the bus. - completion
Likewise, when you say
I am glad that you could make it
I am disappointed that I could not attend the funeral
I am happy that I could help.
you are focusing on the ability to do it, not actually doing it.
answered Feb 7, 2020 at 10:59
This is a special case of the use of the modal verb could in all types of written and spoken speech, which has the following meaning: I am glad that circumstances so developed that you were able to come finally. This expression has a hint of slight friendly reproach.
This meaning of the modal verb could be close to its other meaning, when it indicates that something sometimes happened, for example, Someone could be a good person if he/she wanted to.
