短语精学：

go forward

1. 向前，前进：
The students went forward at dawn.
学生们天一亮就出发了。

2. 进行；取得进展：
Their work is going forward well.
他们的工作正进行得很顺利。

3. 发生：
What's going forward downstairs?
楼下发生了什么事？

4. 被提交：
The suggestion went forward to the board of directors.
建议已提交给董事会。

5. （夏令时间开始时时钟）被拨快：
The clocks go forward in the spring.
春季时钟要拨快。

句子表达：

Take great care, because they must not know that somebody is watching them.
谨慎行事些，因为他们不该知道有人正在监视他们。

take care 注意；小心

eg. He or she should also take care not to share food, drinks and eating utensils.
他（她）同时也要注意，不要与别人分享食物，饮料和其他的餐饮用具。

must not 不可以；不允许；不准

eg. It must not be allowed to do that this time.
这一次绝对不允许此类事情再次发生。