"Which Allow me" or "Which Allows me"?

Context: "My work requires me to be at different areas for different events which allow me to learn ..."

Do I use "allows" or "allow"? Can you provide me the rules/situations in choosing which one to use for future reference? Thanks.

Either one is correct, but the meaning changes. If the verb is plural, the which refers to the events. The events allow me to learn:

• "My work requires me to be at different areas for different events which allow me to learn ..."

Another way to say this:

• "My work requires me to be at different areas for different events, and these events allow me to learn ..."

If the verb is singular, the which refers to the entire prior clause as a situation: the situation of being required to be in different areas is what allows me to learn. In writing, we should use a comma in that case, by the way:

• "My work requires me to be at different areas for different events, which allows me to learn ..."

Other ways to express this:

• "My work requires me to be at different areas for different events, and {this/that} allows me to learn ..."

• "My work requires me to be at different areas for different events, which is what allows me to learn ..."

• "My work requires me to be at different areas for different events, and that {situation, arrangement, ...} allows me to learn ..."

The entire clause is treated as kind of noun which can be referred to by words like which or this or that.

Sentences in which the plurality of the verb does not resolve the references are ambiguous: "I earn decent money, which allows me to live well". Here which could refer to money, or to the entire clause about earning. Whether or not a comma is written influences the interpretation of the written form, and there are ways to say it to emphasize one meaning versus the other.