be to do, be going to do, be about to do辨析

be to do, be going to do, be about to do辨析
1. be to do:
1) 表示事先商定、安排或准备要做的事情。如：The students are to meet at the school gate tomorrow. 明天学生们将在学校大门口集会。
2) 表示可能性，必要、责任、义务、禁止等。如：Her necklace was not to(couldn't)be found. 她的项链找不到了。
2. be going to do:
1) 表示将要发生的事情或打算最近要进行的动作。如：It is going to rain soon. 快要下雨了。
2) 在含有条件状语从句的主从复合句中，主句一般不用be going to，而常用will（第一人称用shall）。如：
The football match will be put off if it rains tomorrow. 如果明天下雨，足球赛将被推迟举行。
3. be about to do:
1) 表示即将发生的动作，在时间上指最近的将来。如：
We are about to start. 我们就要出发了。

The new school year is about to begin. 新学年开学在即。

新概念英语网课
 新概念英语听力
 新概念英语音频

2) 在含有be about to do的句子中，不能再加时间状语。如：
Wrong: The medical team is about to start immediately.
Right: The medical team is about to start. 医疗队就要出发了。

Parents complain about their teenagers' noses constantly in their phones, but they might want to pay attention to their own screen time habits.
A study out Wednesday from the Pew Research Center found that twothirds of parents are concerned about the amount of time their teenage children spend in front of screens, while more than a third express concern about their own screen time.
Meanwhile, more than half of teens said they often or sometimes find their parents to be absentminded when the teens are trying to have a conversation with them.The study calls teens' relationship with their phones at times “hyperconnected” and notes that nearly threefourths check messages or notifications(通知) as soon as they wake up.Parents do the same, but at a lower if still considerable rate－57 percent.
Big tech companies face a growing backlash (强烈反应) against the addictive nature of their phones and apps, the endless notifications and other features created to keep people fastened to their screens.
Many teens are trying to do something about it: 52 percent said they have cut back on the time they spend on their phones and 57 percent did the same with social media.
Experts say parents have a big role in their kids' screen habits and setting a good example is a big part of it.“Kids don't always do what we say but they do as we do，” said Donald Shifrin, a professor at the University of Washington School of Medicine, who was not involved in the study.“Parents are the door that kids will walk through on their way to the world.”
The study surveyed 743 U．S.teens and 1，058 U．S.parents of teens from March 7 to April 10.The range of error is 4.5 percentage points.
【语篇解读】父母总是抱怨他们的孩子太沉溺于手机，其实是他们自身的这种行为影响到了孩子。为了避免孩子对手机上瘾，父母自身应该首先树立好榜样。