Most whales must come up for air after several minutes, ______ a few can stay under water for an hour or more.[ ]

do you find the town you visited yesterday— The town has changed out of all ______ in the past 20 years, acompletely new one in front of me.

I called you at nine this morning, butthere was no answer.— Oh, sorry, I ______ with my sister in theshopping center.

Either you or he _________ to be invited to the party．

My hometown is in Linyi.It is a wonderful place ____ fun.