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Do you think Maths ______ useful subject?
A. is a B. is an C. are a D. are an
Do you think Maths __________ useful subject?
A．is a
B．is an
C．are a
D．are an
Do you think maths ________ ________ useful subject?
[ ]
A．is; a
B．is; an
C．are; a
D．are; an