重点讲解：
1. smell a rat
怀疑有问题；发现不对头；有所警觉；
eg. If I don't send a picture, he will smell a rat.
如果我不寄出照片，他将有所察觉。
eg. Though Lloyd George's behaviour seemed curious, Haig still did not smell a rat.
尽管劳埃德·乔治的行为古怪，黑格仍然没有任何怀疑。
2. there's no need
没有必要；不必；
eg. There's no need for you to feel sorry. You are trying your best.
你不必感到抱歉。你已经尽力了。
eg. There's no need to blow a fuse over such a little problem.
为这么点小事没必要发脾气。
3. for real
真实地；真正地；不是假装；
eg. This is not a fire drill,it's for real.
这不是救火演习，是真失火了。
eg. That's when you know it's for real.
此时你会知道，这就是现实。
