。
She communicates well with her teachers.
Literal
She [topic-は] teachers [with-と] well mutual-understanding [object-を] is-facilitating.
意思の疎通をはかる is a formal expression meaning 'to facilitate mutual understanding' or 'to communicate effectively.' 意思 means 'intention/will,' 疎通 means 'mutual understanding/free exchange,' and はかる means 'to attempt/facilitate.' This is a stiff, formal collocation — in everyday speech, うまくやり取りしている or コミュニケーションをとっている would be more natural. 達 (たち) after 先生 makes the noun plural.