The science of medicine, _____ progress has been very rapid lately, is perhaps the most important of all the science.
— ____ can I deal with such a situation? — Take ____ measure you think best.
The reason why I gave in is ____ if I didn’t.
No matter how fast we worked, ____.
The teacher found ____ difficult to decide ____ he would take with him to attend the conference.
Living things are dying out quickly. Let’s ask ____ destroying them in the past years.