1) Call A Spade A Spade
Sometimes it's good to call a spade a spade, but sometimes it's better to be more diplomatic in what you say.
I should warn you that Sandra calls a spade a spade, so if she thinks you say something wrong or make a mistake, she'll say so.
David has lost a lot of friends for calling a spade a spade.
Meaning: If you call a spade a spade, you tell the truth in a straightforward and direct way, even if the truth is not pleasant.
Etymology: A spade looks like a small shovel, but does not have the same size and capacity of a shovel. Calling it what it a spade is a lot more blunt and direct than making comparisons between a spade and a shovel.
2) Behind the Times
How can we be a successful company if our executives are so behind the times that they don't know what people want these days.
Neil is really behind the times. He doesn't even know what rap music sounds like!
Jim is really behind the times, he still listens to very old fashioned music.
Meaning: If someone is behind the times, they are old-fashioned and their ideas are out of date.
Etymology: The time refers to the trend of a specific time period.
3) Another String to Your Bow
Lots of people learn to teach English so they'll have another string to their bow.
Becky is a broadcaster that decided to learn how to play a musical instrument so she would have another string to her bow.
I've lost my job and I'll have to retrain for something else. I wish I already had another string to my bow.
Meaning: If you have another string to your bow, you have another way of making a living.
Etymology: Probably metaphorical, from the fact that if an archer has a spare string for their bow, they can still shoot an arrow even if their first string breaks.