There was no cheerful Hagrid waiting for them at King’s Cross Station. Instead, two grim-faced, bearded Aurors in dark Muggle suits ... marched them into the station without speaking. "Quick, quick, through the barrier," said Mrs. Weasley, who seemed a little flustered by this austere efficiency.
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He took a vow of silence and leads an austere life at the monastery.
While most kids are partying at college, she practiced austerity during her college years.