The sun rose, as it always ___, in a clear sky.

On the Eve of the Spring Festival, we Chinese people like to play with fireworks, and the noise doesn’t ____ until after midnight．

They are ___ the old houses in order to set up a new teaching building.

Do you have any difficulty ______ these flowers? I’d like to help you if you need.

The visiting professor         giving lectures to students         invited to meetings at times.