My brother is very shy.

我的弟弟很容易害羞！

My brother is a bit introverted.

我弟弟有一点内向！

My brother is timid.

我弟弟很胆小。

My brother is reserved.

我弟弟很沉默寡言。

My sister is kind of quiet.

我妹妹有点安静。

My sister is gentle and quiet.

我妹妹很温和安静。

My sister is a bit blunt.

我妹妹有点迟钝。

My sister doesn't like to stand out.

我妹妹不喜欢引人注目。

It is embarrassing.

真叫人难为情。

Be more confident.

有自信点。

Don't hide behind my back.

不要躲在我后面。

Don't whisper.

不要窃窃私语。

Say it louder.

说大声点。

You need to say what you want clearly.

你必须把你想要的东西清楚的说出来。