"我们一起努力" 可以用英文表达为 "Let's work together" 或 "Let's put in effort together"。
"Let's" 是 "let us" 的缩写，表示说话人与听话人一起做某事。"work together" 或 "put in effort together" 则表示我们要一起努力。
例句：
"Let's work together to finish this project on time." (我们一起努力完成这个项目)
"Let's put in effort together and make this company successful." (我们一起努力，让这家公司成功)