1. Knee-high to a grasshopper 小不点，乳臭未干

例句：Charles started reading when knee-high to a grasshopper. 查尔斯在很小的时候就开始读书了。

2. To have butterflies in your stomach. 紧张，七上八下

例句：Sitting there at my sister’s wedding dinner, I had butterflies in my stomach because I know I’d have to stand up and make a speech. 我姐姐结婚那天晚上举行宴会的时候，我坐在那里心里直感到七上八下，因为我知道我得站起来讲话。

3. To have ants in your pants 忐忑不安

例句：You seem to have ants in your pants. 你看上去心神不安。

【视频原文】

Hello, I’m a very interesting and intelligent man.

And these are insects. Today, these insects and I are going to teach you some idioms in English.

I bet you’ve never been taught by an insect before!

When I was a little boy I loved insects.

Small, wasn’t I?

In fact I was knee-high to a grasshopper.

In English, when we want to talk about someone who is very young or very small we can say they’re knee-high to a grasshopper. Which, as you can see, is not very tall.

Knee-high to a grasshopper.

I’ve got to make a speech… in front of five thousand people. Can you imagine how I feel?

Nervous! I've got that strange feeling in my stomach you get when you’re feeling nervous.

Ah yes, butterflies. That’s how it feels – like I’ve got butterflies in my stomach.

In English, if we’re very nervous about something we have to do, we can say "I have butterflies in my stomach".

To have butterflies in your stomach.

Well here I go… I hope they’re kind to me…

Ah, hello.

I’m going to meet my hero, Mr Bean.

I’m so excited. I’ve got ants in my pants.

Well, not really, but in English if you're so excited about something that you can’t keep still you can say you’ve got ants in your pants.

To have ants in your pants.

Actually, I have got ants in my pants. Arghhh!