Interest is as ________ to learning as the ability to understand, even more so.

Until recently historians assumed that calendars ________ with the advent of agriculture.[ ]

To qualify yourself for this kind of new job, Irecommend that you ________ some online courses.

Susan has been working hard day and night, which ________ her pale face.

I love animals and that’s the reason ______ I hate the people who kill wild animals for money.