妹妹: younger sister, young woman...
兼职: to hold concurrent posts, concurrent job, moonlighting...
小费: tip, gratuity...
太阳能: solar energy...
果然: really, sure enough, as expected, if indeed...
此刻: this moment, now, at present...
使命: mission, long-term task to which one devotes oneself, a calling...
天气: weather...
心得: what one has learned (through experience, reading etc), knowledge, insight, understanding, tips...
大体上: overall, in general terms...
