Stem-changing Spanish c>zc verbs in the present tense

Spanish verbs that end in a vowel + -cer/-cir swap the -c- for a -zc- in the yo form. For example conocer (to know/meet):

There are two common verbs, hacer and decir, that are exceptions to this rule. They have a different irregularity.

Some other verbs affected by this specific consonant switch are:

• conducir (to drive)
• permanecer (to stay)
• ofrecer (to offer)
• producir (to produce)
• introducir (to intruduce)