The doctor told Jack that his wife must stay in hospital for at least two days for observation. Jack ordered a single ward that is prim and quiet.
大夫告诉杰克，他妻子必须留院观察至少两天，于是，杰克要了一间单人病房，既清洁又安静。
2
The ordered crystal structure indicates the existence of nanometer metal particles in the nature and provides direct observation evidence for deep-penetrating geochemistry.