When ____ the education systems of China and Britain,the professor gave a detailed comparison between the two.选项:a、being asked to compareb、asked him to comparec、asking him to compared、asked to compare

英语翻译How ____ do the British ____ ____ ____ ____ ____ when thet first meet? People ____(cheerful) when the president walPeople ____(cheerful) when the president walked past. Remember to close the door when you go out.____ ____ ____ close the door when you go out. When he realized he had won的同义句 When he realized he ____ the ____. When autumn comes ,the ____ the trees turn yellow.(leaf) When the teacher____(enter) the classroom ,they ____(read) English What where you doing when someone Knocked at the door?I ____ ____ ____ ____ ____(接电话) When she was a girl of seven ____ the ____ ____ of seven ____(when/while) i sleep,the earthquake _____(happen) Don't forget ____(close) the door when you leave They ____ (water) flowers when I got to the garden. Be careful when you walk ____ the streetthroughacrossintofrom you must be ____(care)when you cross the street. It happened ____ (rain)when was at the station Please ____(knock)at the door when you come in. Mother ____(sweep) the floor when I left home yesterday. She ____(巡回演出)the USA when she was fourteen. When ___ the first class ____ (begin) every day