用所给词的适当形式填空。
【小题1】I often have good __________ (communicate) with my friends on the Internet.
【小题2】Jim has heard of the famous __________ (Canada) singer called Celine Dion.
【小题3】The boy is __________ (tie) his shoes at the moment.
【小题4】－Has he gone to Paris on __________ (busy) or for a holiday? －I don’t know. But he runs a company there.
【小题5】What great fun the students had __________ (discuss) these difficult problems in class.