1) No strings attached
-The Vanderbilts give each of their children 20,000 dollars a year, with no strings attached.
-I am concerned that the donation has no strings attached, that means the charity can use the money anyway they want.
-Don't go for the free bus tour, there must be strings attached.
Definition: Without conditions or restrictions
Etymology: This expression dates from the mid-1900s, although string in the sense of "a limitation" has been used since the late 1800s.
2) PDA
-Ronald was uncomfortable by the couple practicing PDA.
-Couples that practice PDA should get a room.
-The couple in front of us in the line are showing PDA, they must be European.
Definition: public displays of affection
3) In bed with
-The Senator is in bed with the defense company in order to secure manufacturing jobs in his state.
-Nathan got in bed with a gangster after he needed a loan to pay for his rent.
-The good things about Donald Trump is that he does not need to get in bed with Super Pacs to fund his campaign.
Definition: secretly helping someone and for something in return