She________in her room at 9:00 last night.
–_______________ does a CRH train run? –It runs up to more than 300 km an hour.
You shouldn’t keep a pet _______________ you have enough time to care for it.
___________ the young girl ___________ her parents take regular exercise in order to keep fit.
Generally speaking, a computer works _______________ a human brain.
Nowadays, children under 1.4 meters _______________ be free to take buses in some cities.