Before a problem can be solved，it must be obvious____the problem itself is.

－Would you be here to attend the English party this evening?－Yes, we ______ .

IT course is taught in all levels ofschools, _____ we have entered the information society and we must fit in withit.

He_____ some German while he was away on a business trip in Berlin.

Didn’t you enjoy the film— Not at all. __________, I was disgusted (使厌恶) by the amount of violence in it.