The words “racecar”， “kayak” and “level” are the same  ________ they are read left to right or right to left.

A.since B.though C.unless D.whether

I didn't believe I could make it u________ I got to the top of Mount Hua.

It has been five years ________ I saw my primary school classmate last time.

I was writing a diary w________ my mother was watching TV yesterday evening.

Keep on taking exercise,  ________ you will become energetic.

We can enjoy the books in the reading room, ________ we can't take them out.

The city is covered with fog and haze more often than ever, ________ we must take actions to stop it.

(2019吉林省卷)On school nights, I either do my homework ________ read books. I never watch TV.

(2019安徽改编)Our business won't improve u ________ we offer better services to our customers.

—My parents are crazy about Beijing Opera.  How about your parents?

—________ my dad ________ my mom likes it. They prefer soft music.

A.Neither; nor B.Both; and C.Either; or D.Not only; but also