The ground is wetIt must have rained last night, ______it?[ ]

Radium salts，which have been found to______ in bones，give rise to bone cancer.

The girl __________ all her savings tothe people in the Southwest for the serious drought(旱灾).—What a donation and what a nice girl!

It was cold.The wind ___ hard and no one could be seen around

She went to the game late .______she left her ticket at home .