中间应该是of course当然 吧?不然不太通唉。
这句话翻译过来就是,那个,当然,是个好消息。
断句是which that, of course, is wonderful news。这样的话,这应该是半句话,that是主语,代指前文说的news;which 表示这句话是从句。
造句可以这样造:i brought u one good news and one bad news. first, ur sister just got engaged, which that, of course, is wonderful news. however, her fiancee[未婚夫]simply disappeared right after the engagement.
which 可能引导一个定语从句,而that是跟 of cause连在一起的,可理解为the cause。你这句活写全了吗?