What they are ____ about is which comes first: the chicken or the egg?

Whattheyare____aboutiswhichcomesfirst:thechickenortheegg?

Thatisa____pointofview.Idon’tagreewithyou

During these ten years, many new methods have been ___ in thefield of foreign language teaching.

Part IV Translation

By making vehicles lighter in weight aluminum has greatly reduced the amount of fuel needed to move them, (Passage Two)