 Re: decide
Not in the same clause, no. Look at the examples above. The verb in the clause with since is always in perfect aspect.
What I'm saying is that it would be unusual to use the verb decide together with since, as, generally, you know when the decision was made. I've given a couple of examples when it might be possible to say eg since then, indicating that I don't know exactly when the decision was taken (or if he's actually done anything about it. But generally a decision happens at a specific moment - which you know about - and it's what you decided to do that happens afterwards, as in the last example.
As always, you must consider the context. language use doesn't happen in a vacuum. It's affected by the situation. The problem with your examples is that the context is never provided. If you give one, then you'll find it's much easier to understand why certain forms are used rather than others. That's why my answers always add one. |