问题补充：
单选题Studentsshouldbyallmeans______theirstudiesthoughtherearealotofentertainmentsinvitingthem.A.devote toB.fix onC.concentrate onD.pay their attention
答案：
C解析concentrate on全神贯注于, 其他三个短语也有类似的意思, 但结构为: devote one’s life/ oneself…to (doing) sth专心致力于; fix one’s eyes/ attention on sth ; pay (much)attention to (doing ) sth
