Complete the following sentence with a (compound) word derived from the one(s) given in bracket.
He is （ ） in company, but you will never believe that he is somewhat sad when he is alone. (cheer)
【正确答案】：CHEERFUL
【题目解析】：
根据前文is可知后面应填cheer的形容词形式cheerful高兴的，愉快的。句意：他在公司的时候很开心，但你绝对想不到当他独自一人时会有些悲伤。