据说....it is said that...

"they say,..." 他们说， "one says, ..." 有个人说， or 一个人说，depends on the context "people say, that..."人们说 "i would say..."我会说 man sagt? Auf Englisch ich glaube ist "people say", oder? "i would say..." ist auf Deutsch "Ich würde sagen", oder?

听说。。。。 This refers to hearsay.

they say = 他们说 one says = 有人说 one man says = 那个男人说 people say, that.. = 人们说那只 or 有些人说，... I would say.. = 我会去说

"they say,..." 他们说…… "one says, ..." 某人说…… "people say, that..."人们说…… "i would say..."我想要说……