一般是用It is +被强调部分+that或who来强调：
It is Bob that tells me this message.是鲍勃告诉了我这个消息.
It is in the classroom that we have our English.我们在教室里上英语课.
如果是强调动词,用do或does：
I do like milk.我确实很喜欢牛奶.