My most devoted friend, Professor Yang, _______ often go hiking when he lived in the mountain that was covered with forest.

I _____ you somewhere before , but your name has escaped me _____ moment . 

－Mom’s gift? She _______ have chosen a better one for me.－She must be very happy to know it.

The girl was drowned unfortunately. She ____, though, because there were so many people standing on the banks at that moment.

The man is weak in health, and is advised by the doctor ________more exercise.