speak louder还是loudly

是speak loudly，例如：

1.Foreigners often complain that Chinese people speak loudly. Why?外国人常常报怨中国人说话声音偏大，为什么？

2.Well, I will speak loudly of your love.那麽我会大声地说出对你的爱。

3.We should take care not to speak loudly in the classroom.我们务必不要在教室里大声讲话。