(1) aloud常与动词read和think连用，表示“出声地”。

• She has a very good pronunciation when she reads aloud .
  她朗读时发音非常好。
• A: What did you say?
  你说什么？
  B: Oh, nothing, I was just thinking aloud .
  哦，没什么，我只是在自言自语。

 (2) loudly和loud一样，用来指声音的音量。

• When they are arguing, they talk so loudly that the people in the next flat can hear every word.
  他们争论时，讲话声音那么大，隔壁房间里的人都能听清每一个词。

 (3) loud在日常会话中常用在动词后，代替loudly，常一起用的动词是talk, speak, shout, laugh等。另外，loud常用在loud and clear短语中。

• Don't talk so loud — you'll wake the whole street!
  不要这么大声讲话——你会把整条街上的人都吵醒的！