Father won’t agree to fly to Paris for the holiday ----it is ________ expensive.

I have little doubt about his competence; ______, he is well-qualified for the job. 

 Smallpox, a kind of disease, has now died ________.

While typing, Helen has a habit of stopping _____ to give her long and flowing hair a smooth.

A car engine cannot run smoothly without motor oil.____ our body cannot function efficiently without vitamins.