下列计算正确的是( )
A:7a+a=7a2
B:3x2y﹣2yx2=x2y
C:5y﹣3y=2
D:3a+2b=5ab
— Listen! Who ____ (sing)in the next room?
— It's Miss Brown,
Bill became a(n)____ ____ at the age of 35.
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