He saw a notice at the entrance ____ , “No spitting”[ ]

The Japanese Emperor has made a rare televised address to his disaster-stricken country, and_____ his deepest concern about the dangerous situation at the nuclear power plant, calling for people to overcome hardship.

I can play the guitar, _________ his brother.

There is so much noise around his flat that he feels mad.

One of the difficulties we have Englishis how to remember new words and expressions. A.to learn B. in learning C. learn D. learned