Mike lost his key. ______ couldn’t enter the room.

We often go to park ______ Sunday afternoon.[ ]

Zhong Nanshan, the famous medical scientist, has devoted most of his life useful ways in treating cough diseases.[ ]

He has ______ for some years, but his _____ still makes us very sad now.

Maggie wanted an evening job that would allow her to ______ her son during the day.