Here are your answers:

**26-** B (stomach) - The pronunciation of the "ch" in "stomach" (which is pronounced as /k/) differs from the "ch" sounds in "beach," "which," and "speech" (which are pronounced as /tʃ/).

**27-** C (dirty) - The emphasis pattern of "dirty" differs from the others, which are stressed on the last syllable, while "dirty" is on the first.

**28-** D (important) - The main stress is on the second syllable, while the others (A, B, and C) are all on the second syllable.

**29-** D (practise) - The main stress is on the first syllable, while the others (A, B, and C) have stress on the second syllable.

**30-** B (taekwondo) - The stress pattern is different; "taekwondo" has the stress on the last syllable, while the others (A, C, and D) have the stress on the second syllable.

Your answers:
**26- B**
**27- C**
**28- D**
**29- D**
**30- B**