Smooth sailing
Something is going well and is having no problems.After we left the city it was smooth sailing on the highway until we got to our destination.
Smooth (something) over smooth over (something)
To make something better or more pleasant.We tried to smooth over the problems between our supervisor and the sales staff.
Smoke (something) out smoke out (something)
To find out the facts about something.We finally were able to smoke out the reason why our boss left the company.
Smoke (someone or something) out smoke out (someone or something)
To force someone or something out with smoke.We smoked the rats out of their nests with the smoke.
Smoke and mirrors
Deception and confusion.The accounting department used a system of smoke and mirrors to hide their illegal activities.
Smile on (someone or something)
To be favorable to someone or something.The weather is smiling on the farmers in our area.
Smell a rat
To become suspicious.I do not know what my colleague is doing but something seems strange. I think that I smell a rat.
Shoulder to shoulder
Side by side, with a shared purpose.The firefighters worked shoulder to shoulder to help prevent the house from burning.
Shotgun wedding
A forced wedding.The young couple were forced into a shotgun wedding by the girl's father.
Shot through with (something)
Containing something.The drink was shot through with some chemicals which I did not know.