（合并句子） ICQ is a chatline.People use ICQ to have conversations.
问题描述：
（合并句子） ICQ is a chatline.People use ICQ to have conversations.
（合并句子）
ICQ is a chatline.People use ICQ to have conversations.
People use ICQ ________ ________ _________ _________ to have conversations.
答
which(that)is a chatline