Liu Ying is good at singing. She sings ______the famous singer, CoCo.

Mum, my friends are waiting for me outside. May I go out to play with them?— Yes, you , but be careful, please.

What does your brother look like?–He is.

I don’t understand ______ such a silly question in class yesterday.

.He said that not until the heavy snow blocked the express ______ how serious the weather was.