____ directly to the sun in summer will do great harm to our skin.

The poor boy could do nothing but ___ at the corner of the street.

The salesman scolded the girl caught ______and let her off.

The old professor travelled from one school to another, _______ first-hand information about the education situation in China. 

____ to the Qin Dynasty，the traditional crosstalk shows have made people roar with laughter.