—____the Smiths____(decide) to go to China for their holiday?
—Yes.they have.
若3名女生,5名男生排成一排拍照,问:(用数字作答)
如图,∠1=____°
下列关于病毒的说法,错误的是( )
核能是指原子核发生____ 或聚变时所释放的能量.