Sentences that I didn't understand...

[Kerim]

Oh, this forum is really too crowded. My topic has slipped pretty. Please, you answer it...

[Kerim]

[Kerim]

Heeeeeeeeeeelp!!!

[Casiopea]

The phrase passing trade is a euphemism for clients/customers that pass by on the street and trade money for sex. Synonyms: john (US), punter (UK).

EX: [Prostitutes] must all go and stand on street corners and pick up passing trade ...

EX: But the roundabout girls are still ... attracting only passing trade.

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The sayings that is to say and that says something are not related. The latter saying is short for that connection of ideas says something significant:

It was a very messy business. So messy, in fact, it made Bouchard nervous. And the fact that Bouchard, a guy who doesn't scare easily, was nervous about the events that had taken place tells us how significant the danger or degree of danger involved.

[Kerim]