He said it was _____ impossible to buy the novel which was _____ worth reading.

____ the search engine just gave me some brief introductions rather than the whole content of the book to read.

Noise is unpleasant, _____ when you are trying to sleep．

—Mom，dad is smoking again!—Well，let him cut it ________ gradually since old habits die hard.

Many questions were asked，particularly ______ the cost of the new plan.