题目

一个角的补角比它的余角的3倍多30°，求这个角的度数为多少？ 答案：设这个角的度数为x， 根据题意得：180°﹣x=3（90°﹣x）+30°， 解得：x=60°． 【点评】此题考查了实数的运算，熟练掌握运算法则是解本题的关键． 完成句子，使改写后的句子完整，并与原句意思相符，注意每空只填一个单词。 The girl had to look after her grandmother when her parents were out． The girl had to ________　________　________ her grandmother when her parents were out．