I have this doubt when to use these two terms; for example:
If I had been with you, I might be taking care.
or:
If I would have been with you, I might be taking care.
Which is correct, and, if there is a difference between the two, how would you explain that difference?
Best Answer
A very thoughtful and hard question indeed; it pushed me to research a bit on the subject Continuous Conditional.
Your first example is a past perfect continuous sentence. In general, it is used to indicate an action was happening before another action happened. However, it can also be used to indicate past unreal condition. For example:
But fortunately, he was not talking to him when he said that and that's how he missed my punch.
So according to this theory, your first sentence which is
is absolutely meaningful and grammatical.
Now, there is a vital fact when using these type of constructs as described by data.grammarbook.com,
So this theory, in a nutshell, says you can't use "would" part with the "if" clause, rather it should be used in the result clause. So, according to this theory, your second sentence stands incorrect.