Mr. Wang _______drive to work, but now he _______there by bike to keep healthy.

A．used to; is used to going

B．used to; is used to go

C．was used to; is used to going

D．was used to; is used to go

“由第三人向债权人履行债务”时，如履行债务不符合约定应( )。

A．债务人不承担违约责任

B．由债权人追究第三人的违约责任

C．由债务人向债权人承担违约责任

D．由债务人追究第三人的违约责任