I have ten languages on the go, right? So what do I do the day after starting a new one—Polish? I immediately carry on where I left off, with Polish.
Why is that?
Maybe I’m like a dog with a bone. I enjoy doing the same thing over and over. Or I like novelty. The new language is still new.
Another reason could be that it’s the type of activity—copying i+1 sentences in a notebook—that attracts me. If so, then it behooves me to have different sorts of activities and/or resources on the go for each language.