Yesterday afternoon I rushed into a bookstore _____ a shelter from the rain without noticing what kind ofbookstore it was [ ]

When the temperature drops to 0℃, ice ________ on the surface of water. [ ]

The mother often tells her son to be a good boy, warning him to _____ trouble.

I wonder, Mr Adams, ______ you’d mind us asking a few questions.—______I am all ears.

The house _______ Lu Xun used to live in is now the museum.