Who (subordinator )
who live in the glass house (adjective clause)

Analysis of the sentence "People who live in glass houses must not throw stones at others."

Main clauses:
- People must not throw stones at others.

Subordinate clause:
- Who live in glass houses.

Type of subordinate clause:
- Adjective clause

Explanation:
The main clauses in the given sentence are "People must not throw stones at others." This clause expresses a piece of advice for people not to criticize or judge others when they themselves are not perfect. The subordinate clause in this sentence is "who live in glass houses." This is an adjective clause that modifies the noun "people" and provides additional information about the people being referred to. The adjective clause tells us that the people who are being advised not to throw stones at others are the ones who live in glass houses.

The phrase "live in glass houses" is an idiom that means to be in a position where one's flaws or faults are easily visible or exposed. The use of this phrase in the subordinate clause emphasizes the idea that the people being advised not to criticize others are themselves vulnerable to criticism. The sentence, therefore, carries a message of humility and caution, reminding us that we should refrain from judging others when we ourselves have weaknesses and faults.

In conclusion, the given sentence contains a main clause that gives advice and a subordinate clause that provides additional information about the people being referred to. The subordinate clause is an adjective clause that modifies the noun "people," and it emphasizes the idea that the people being advised not to throw stones at others are themselves vulnerable to criticism.