What do all of these things have in common

a shoe, a suitcase, a bit of ink,

a painting, a child’s eyes at a chalkboard,

a bit of chalk, a bit of

bone in ash.

The thing the have in common is about a child and a picture.

Explanation:

From the things listed, there is a possibility that it is talking about a child's admiration of a wonderfully drawn painting on the chalkboard. The picture shows an image of someone wearing a shoe and with a suitcase.

The admiration of the child stems from the fact that, he could have been the one who drew it and was only trying to be sure that it was worth it after all the stress he passed through to draw the picture using a bit of ink and some chalks.

1- cleans/ tidies up

2- were

3-would be

4- had known

5-takes

6-must be/ have to be/should be