。
Mr. Suzuki was scheduled to give a speech that afternoon.
Literal
Suzuki-Mr. [topic-は] that day [of-の] afternoon [in-に] speech [object-を] give [scheduled-ことになっていた].
~ことになっている is a key scheduling/arrangement pattern: 'it's been decided/arranged that X,' often used for external rules, schedules, or social agreements (not personal decisions, which use ~ことにする). In past-continuous ~ことになっていた: 'was arranged/scheduled to.' Common in narrative past tense.