Hi there, should I use "have been able to do" or "could do" in the following context?
If you are talking about what has (or in this case hasn't) happened in the past, it is clearer to use "have been able to do". In the first sentence, you should delete the word "by".
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
If you are talking about what has (or in this case hasn't) happened in the past, it is clearer to use "have been able to do".
In the first sentence, you should delete the word "by".