29. He was busy preparing a speech , only _______ once in a while to rise from the table for a tea .

A．stopping

B．to stop

C．to have stopped

D．having stopped

如果某订单有售后或 * * 正在处理，则在所有售后或 * * 结束后的第几天结算货款。（）

A、4

B、3

C、1

D、2