everybody began to laugh and sing为什么laugh和sing不用过去时

everybody began to laugh and sing为什么laugh和sing不用过去时 everybody began to laugh and sing.为什么后面不是过去时? At that moment ,everybody began to laugh and sing . everybody began to laugh and sing 中的began 是及物动词还是不及物动词? At that moment,everybody began to laugh and sing同义句、、快些嗯. sing,look,laugh,talk的过去时,急用! 英语新概念小问题第二册第九课有一句：at the moment,everybody began to laugh and 英语翻译Sing with me,sing for the year sing for the laugh and si He often make us ____(laugh).laugh为什么用原行不用to laugh. at last sha made the baby()and began to laugh The baby couldn't stop ____(laugh)while her mothe___(sing)to At last he b________a singer and began to sing song.