Explain: “Once in a while, of course, he had to put his foot down, like when she wanted to get a job or go back to school or buy American clothes.”
The quote in question comes from Chitra Banerjee Divakaruni's text Arranged Marriage. Given that the quote comes from a text on the subject of arranged marriages, the quote has a very definitive meaning.
The relationships between couples in arranged marriages are typically patriarchal (meaning the man of the family makes all rules and the woman is expected to live according to them without question). Given the desire for some women to take control in their lives and marriages, some women have begun to speak out and not allow their husbands to have complete say in the marriage. Some men, in arranged marriages, have allowed their wives to do things which would not normally be allowed. That being said, while certain "little" things are okay, others will always remain off-limits.
As for the quote, the narrator is implying that while the husband has allowed his wife to do some things not necessarily typically accepted, the wife (in the text) is not allowed to go to school, buy American clothes, or get a job. These are the things typically kept from women who are involved in arranged marriages. One could assume that certain private behaviors are allowed by the husband, but, when it comes to public behaviors, certain things are off-limits.