根据括号中所给的汉语，写出单词的正确形式，使句子意思完整。

小题1:They were playing _________ ( 吵闹 ) outside.

小题2:It has been in _________ ( 服务 ) since 2000.

小题3:Have you ________(意识到) this serious mistake now, guy?

小题4:_______ ( 闪电 ) started a big fire in a house.

小题5:The _________(政府) has taken action to prevent people cutting down the trees.

比赛中，A4已达5次犯规，应通知他并必须立即离开比赛。他必须在（）秒钟内被替换。

A、30秒

B、50秒

C、15秒