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Don't keep your mouth ___ if you want to improve your spoken English.

  A. shut        B. shutting        C.shutted       D. to shut

Don’t keep your mouth ___ if you want to improve your spoken English.

A. shut   B. shutting   C. shutted   D. to shut

Don’t keep your mouth ________ if you want to improve your spoken English.

[　　]

Don’t keep your mouth ________ if you want to improve your spoken English.

[　　]