政府军与叛军发生了冲突。

Government troops ___clashed with rebel soldiers.

许多年轻人因为晚上必须回家的时间与父母发生争执。

Many young people ___clash with their parents over what time they must be home at night.

从一开始，他们俩的性格就格格不入，关系一直在恶化。

From the very beginning their two characters ___clashed and the relationship had only been deteriorating.