The answers to the clues below will have something in common.

 

1. Au pair

2. Shoe-making innovation

3. Strongbox on a windowsill

4. Feature of high density real estate

 

Answers:

 

1. Foreign domestic

2. First last

3. Dangerous safe

4. Little lots

 

Credits:

1: Henry Hook

2-4: Emily Cox and Henry Rathvon

        OPPOSITE ATTRACTION