用法:
1 any of a series of horizontal layers, esp of rock in the earth's crust 层; （尤指）岩层.

用法:
2 level or class in society （社会的）阶层:
a gathering of people from a variety of social strata 不同社会阶层的人的集会.

• in one way or another(in some way or other)
• in one's grasp(within one's grasp)
• in one's head(into one's head)
• in one's life(in one's time)
• in one's line of business(in one's line of country)
• in one's mind(on one's mind)
• in one's power(within one's power)
• in one's time(in one's own time)
• in one's track(on sb's track)
• in one's travels(on one's travels)
• in one's way(on one's way)
• in order that(so that)
• in order(in orders)
• in part(in good part)
• in part(in parts)
• in pickle(in a pickle)
• in place(in one's place)
• in possession of(in the possession of)
• in power(in one's power)
• in principle(on principle)
• in proportion as(in proportion to)
• in quantity(in large quantities)
• in rank(in the ranks)
• in reality(in truth)
• in reason(within reason)