He bought a house for his children ________
B
本题属于动词不定式复合结构做后置定语。in不可省略。句意:他买了一套房子给孩子们住。
Sofarscientistshaveonlyacquired________understandingofthephysicalprocessesthatcauseearthquakes.
Thewoundedsoldierswouldrecoverquicklyiftheywerewell________.
TheFrenchmaintaina________separationofpersonalandprofessionallife.
Therearemanysalesthisseason,duringwhichstoreswilllowertheir_______prices.