look的过去式是什么？
vt. 看；期待；注意；面向；看上去
vi. 看；看起来；注意；面向
look的变形属于规则变化，look的过去式和过去分词是在动词原形后面加_ed,即looked。
例句：
1. He looked straight ahead and overtook a lumbering lorry.
他眼睛直视前方，加速超过了前面一辆慢吞吞行进的大卡车。
2. There was a long silence, and my father looked shamefaced.
沉默持续了很长时间，而我父亲看上去面带愧色。
3. He looked at Ellen, breathing evenly in her sleep.
他看着埃伦，她正呼吸均匀地睡着。
