The pronunciation of the past tense ending follows similar rules to those for the third person present tense ending described above: if the base form ends in or then a new syllable or is added (as in "drifted", "exceeded"); if the base form ends in an unvoiced consonant sound other than then the ending is pronounced (as in "capped", "passed"); otherwise the ending is pronounced (as in "buzzed", "tangoed"). Consequently, in the 17th and 18th centuries, the latter two pronunciations were routinely spelled "-'d", but "-ed" was later restored.