I'm going to do the roll call now. 
下面开始点名。
Did the teacher do the roll call yet?老师点过名了吗？
I'm taking attendance. 我正在点名。
Say 'here' when I call your name. 我点到大家名字的时候请答“到”。
Raise your hand when I call your name. 我点到大家名字的时候请举手。
Why are you late?你为什么迟到？
Don't be late./Don't come to class late.不要再迟到了/上课不要再迟到了
Try to be in class on time. 尽量按时来上课。
You've been absent for three days straight. Where have you been?你已经连续三天旷课了，你到底去哪儿了？
Let's get started./Let's get going. 我们开始吧/让我们开始
Let's start with a little review from last time. 首先让我们复习一下上次学习的内容。
Who knows the answer to the first question?谁知道第一个问题的答案？
Who wants to go first?谁想第一个来？
We'll finish this section today and start the next one tomorrow.今天我们将学完这一部分，明天开始学习下一部分。
I need you to get into groups of three or four. 我需要大家分成三到四人的小组。
You can work on the assignment alone or with a partner. 你可以自己完成这个任务，也可以找一个搭档一起完成。
We'll have a review day at the end of the week. 本周末我们将进行复习。


Dialogue:
A: I checked class started at eleven. Why are you late?据我所知，我们是11点开始上课，你为什么迟到？
B: I'm sorry, Mr Smith. I couldn't find my history book. 对不起，史密斯老师。我找不到我的历史书了。