I was sad to work although the weather is marvelous. There were many people enjoying sunny day outside where I went . I have spent way too many times teaching with passion. But it is not enough to teaching to refill my zest of life. = But it's not enough to refill the zest in my life.  That is why I try to learn something. Nowadays I concentrate on learn english = on learning English. I am not sure you can feel how I am trying to. I am memorizing about hundread words once a week despite no time to study. = I memorize a hundred of words once a week despite my limited time. Using a brain is getting to gain an unimaginable stimulation .(The underlined sentence is confusing. Please rephrase it.)