____________ have you been married—For twenty years.

The number of people invited to the party________fifty，but a number of them________absent for different reasons.[ ]

I can’t remember the words all the time .—_________________

Could you please________ my pet dog when I’m out

填入横线上的句子，与上文衔接最恰当的一句是（ ）随着市场经济体制的日臻完善，利用先进技术提高产品的科技含量以增强市场竞争力，已成为各企业集团的共识。_________________________________________ 。