Which syllable carries the main stress in the words 'diplomat' 'successful' 'accumulative' 'diplomatic' 'comfortable' 'increase' 'diplomacy' 'refer'?

Diplomat: first

Successful: second

Accumulative: second

Diplomatic: third

Comfortable: first

Increase: second for the verb; first for the noun

Diplomacy: second

Refer: second (note that "reefer" has the stress on the first syllable)