"interfere" in the verb sense
come between so as to be hindrance or obstacle
"Your talking interferes with my work!"
2. intervene, step in, interfere, interpose
get involved, so as to alter or hinder an action, or through force or threat of force
"Why did the U.S. not intervene earlier in WW II?"
Source: WordNet® (An amazing lexical database of English)
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