Is there a way to strengthen skills at one time?
I have multiple skills that are very low and it takes much too long to go through each individual section and strengthen that set of skills. Is there a way I can do 1 test and sill strengthen all my skills at once?
On the right side of page (when looking at your skills), there's a button that says "Strengthen skills" right underneath the chart of your progress. If you click that, you work on all of your skills at once. However, because you'll only get a word or two from each weak skill, it'll often seem like it's not strengthening anything and may seem to take longer.
You don't have to keep all of your skills at full strength though if you think you already know the material well. There's no penalty for having a colourful tree, and you can continue doing new lessons regardless of the strength of your other skills. Just practice what you're having trouble with, and you'll be good. :)
Or you can just click the desired lesson and then choose to do flip cards. It is quicker and it strengthen your skills. You would get no exp. But it would be quicker than doing all of them manually since you would have to do every one of them multiple times if they are that low