Apt word to substitute for each of four black squares to make sense of the across answers on either side of them

Question:

Answer:

BRIDGE

Length:

Similar Crossword Questions:

Word needed to be added to 12 appropriately placed answers in this puzzle for their clues to make sense
Row of black squares preceding or following six puzzle answers, thereby completing them
Where GIs fought Charlie[LAST WEEK: "Lady X" was Ingrid Bergman, whose first name is revealed in the circled squares (IN + GRID). Seven of her one-word movie titles can be seen "straddling" black squa
Angle irons graphically represented by four sets of black squares in this grid, and by letter formations starting in the four longest answers
Word to add to each theme answer that will make sense of its clue
Apt adjective for today that's needed to make sense of eight puzzle answers
Word that precedes six other answers in this puzzle
Higher pair of black squares in this grid, typographically
Word after pack or black
Driveway stuff (and word that's hidden in this puzzle's four longest answers)
Word after by or side
Lower pair of black squares in this grid, typographically
They make no sense
Word with black and blue
Word with black or chick
Word to a black sheep
Word hidden in this puzzle's longest answers
Word that can follow the ends of the answers to asterisked clues
Final (and a word that can precede the first word of this puzzle's longest answers)
Word that can precede the first word of the answers to the asterisked clues
Word on either side of "de la"
They make sense
Word with cast or side
Word that can be inserted in "mound" to make a synonym for "stagnant"
Observe Black Friday (and a chunk of the eight longest answers)