Children under 12 years of age in that country _____ be under adult supervision when in a public library. [ ]

下列各句中，加横线的成语使用正确的一项是

They believe that there is __________ in the world.

No matter who you are and what are you, ________, we should remember that “being” and “doing” are much more important than “having”[ ]

Look! There is a monkey eating ________ apple in the tree.—En, ________ monkey is very cute.